subject:( Microbiology)

1. Green, Julia Elizabeth. A microbial diversity survey of a natural iron seep within Big Bend Ranch State Park, Texas.

Degree: 2017, Sul Ross State University

URL: http://pqdtopen.proquest.com/#viewpdf?dispub=10249414

► A perpetual spring containing an orange biofilm composed of microbial sheaths was examined utilizing both geochemical and biological techniques. Big Bend Ranch State Park,… (more)

Subjects/Keywords: Microbiology

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APA (6^th Edition):

Green, J. E. (2017). A microbial diversity survey of a natural iron seep within Big Bend Ranch State Park, Texas. (Thesis). Sul Ross State University. Retrieved from http://pqdtopen.proquest.com/#viewpdf?dispub=10249414

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Green, Julia Elizabeth. “A microbial diversity survey of a natural iron seep within Big Bend Ranch State Park, Texas.” 2017. Thesis, Sul Ross State University. Accessed April 16, 2021. http://pqdtopen.proquest.com/#viewpdf?dispub=10249414.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Green, Julia Elizabeth. “A microbial diversity survey of a natural iron seep within Big Bend Ranch State Park, Texas.” 2017. Web. 16 Apr 2021.

Vancouver:

Green JE. A microbial diversity survey of a natural iron seep within Big Bend Ranch State Park, Texas. [Internet] [Thesis]. Sul Ross State University; 2017. [cited 2021 Apr 16]. Available from: http://pqdtopen.proquest.com/#viewpdf?dispub=10249414.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Green JE. A microbial diversity survey of a natural iron seep within Big Bend Ranch State Park, Texas. [Thesis]. Sul Ross State University; 2017. Available from: http://pqdtopen.proquest.com/#viewpdf?dispub=10249414

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

2. Morton, William Grant. Isolating mycorrhizal fungi from Spiranthes vernalis for subsequent in vitro seed germination.

Degree: 2016, Southern Illinois University at Edwardsville

URL: http://pqdtopen.proquest.com/#viewpdf?dispub=10010820

► The Spring Ladies’ Tresses orchid’s (Spiranthes vernalis ) range extends throughout eastern North America. Although the taxon’s distribution is reportedly widespread the species is… (more)

▼ The Spring Ladies’ Tresses orchid’s (Spiranthes vernalis ) range extends throughout eastern North America. Although the taxon’s distribution is reportedly widespread the species is considered threatened or endangered in many areas throughout its range and is reportedly only found in small populations in old prairie remnants, mainly next to railways. One goal for any conservation program is to successfully increase population numbers, possibly by re-introduction of plants into existing populations. It is commonly known that orchids form unique relationships with mycorrhizal fungi and the association is often essential for orchid seed germination and enhances seedling survival and growth rate. The intent of this study is to isolate and identify mycorrhizal fungi associated with Spiranthes vernalis individuals from a population in Madison County, Illinois. The fungi were isolated by excising fungal pelotons from the roots of an adult orchid because of the growth rate and morphology of the fungal isolates,. Fungi assignable to the ubiquitous genera Ceratorhiza and Epulorhiza were isolated. After ITS sequencing of fungal DNA BioEdit Sequence Alignment Editor an NCBI GenBank BLAST (blastn) search was used to confirm the identities of the mycorrhizal fungi found to be in association with the Spiranthes vernalis were Ceratorhiza (Ceratobasidium sp. UAMH 9847). Seeds from three individuals were plated with four fungal types on specialized media to see if any fungi and seed combinations had greater germination rates than other combinations. The percent of germination was calculated based on seed counts and the stage of seed development. Identification of the superior fungi will allow more seeds to be germinated and seedlings grown for eventual transplantation into their native Illinois populations. One of the fungal isolations did in fact germinate seeds with higher success with one of the seed sets used. Overall, each of the Ceratorhiza spp. isolates germinate well with at least one seed set with higher success than the other two seed sets. In addition, after nine months (±one week) the seed germination experiment was split into two groups for one month; cold stratified at 4°C with no light, and room temperature ±21°C with a photoperiod of 8 hours a day. This was done to investigate if additional cold stratification was beneficial to the germinated seedlings or if that was the right time to expose germinated seedlings to light. This cold stratification and light exposure treatment resulted in having no a distinct effect on the germination rates. To further confirm that the Ceratorhiza spp. used in the germination experiment was truly responsible for success in germination, re-isolation of the fungi was attempted and successful, but yet unconfirmed by ITS sequencing.

Subjects/Keywords: Microbiology

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APA (6^th Edition):

Morton, W. G. (2016). Isolating mycorrhizal fungi from Spiranthes vernalis for subsequent in vitro seed germination. (Thesis). Southern Illinois University at Edwardsville. Retrieved from http://pqdtopen.proquest.com/#viewpdf?dispub=10010820

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Morton, William Grant. “Isolating mycorrhizal fungi from Spiranthes vernalis for subsequent in vitro seed germination.” 2016. Thesis, Southern Illinois University at Edwardsville. Accessed April 16, 2021. http://pqdtopen.proquest.com/#viewpdf?dispub=10010820.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Morton, William Grant. “Isolating mycorrhizal fungi from Spiranthes vernalis for subsequent in vitro seed germination.” 2016. Web. 16 Apr 2021.

Vancouver:

Morton WG. Isolating mycorrhizal fungi from Spiranthes vernalis for subsequent in vitro seed germination. [Internet] [Thesis]. Southern Illinois University at Edwardsville; 2016. [cited 2021 Apr 16]. Available from: http://pqdtopen.proquest.com/#viewpdf?dispub=10010820.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Morton WG. Isolating mycorrhizal fungi from Spiranthes vernalis for subsequent in vitro seed germination. [Thesis]. Southern Illinois University at Edwardsville; 2016. Available from: http://pqdtopen.proquest.com/#viewpdf?dispub=10010820

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Oklahoma State University

3. Suresh Rathod, Rachana Ramila. Structure-function relationships in the photoactive yellow protein family of photoreceptors.

Degree: 2016, Oklahoma State University

URL: http://pqdtopen.proquest.com/#viewpdf?dispub=10138974

► The amino acid sequence of a protein determines its three-dimensional structure, which in turn determines its functional properties. An intensively studied but still partially… (more)

▼ The amino acid sequence of a protein determines its three-dimensional structure, which in turn determines its functional properties. An intensively studied but still partially unresolved question is how the structure of a protein relates to its functional properties. Here we use photoactive yellow protein (PYP) as a model system to examine questions on protein structure-function relationships. PYP is a bacterial blue light photoreceptor, a prototype of the diverse PAS domain superfamily, and a model system for functional protein dynamics. The work in this thesis was directed at three aims: (1) developing tools to identify the structural change that triggers intramolecular proton transfer during the PYP photocycle; (2) the functional role of PAS-conserved residue Ile39 in PYP; and (3) determining to what extent the extensively studied structure-function relations in the PYP from Halorhodospira halophila apply to the PYP from Rhodospirillum centenum. (1) The molecular events that cause directional proton transfer in proteins are largely unknown. We develop tools to allow the testing of the specific hypothesis that the disruption of the Tyr42-pCA hydrogen bond during the PYP photocycle causes proton transfer. We developed an effective approach for obtaining Tyr-D₄-labeled PYP that can be used in infrared studies to identify Tyr side chain signals. (2) The PAS domain superfamily is defined by weak but characteristic amino acid sequence conservation, but the functional role of PAS-conserved residues remains poorly understood. We examined PAS-conserved residue Ile39 through biophysical characterization of the I39A PYP mutant. This work revealed that Ile39 is at the core of a set of hydrophobic interactions conserved in PAS domains, is not an essential part in the transmission mechanism of allosteric structural changes during PYP signaling and affects both signaling kinetics and folding cooperativity. (3) We found that structure-function rules for Hhal PYP qualitatively transfer to Rcen PYP, including the role of Glu46 as the electrostatic epicenter for driving conformational changes. The resulting set of Rcen PYP mutants with altered photocycle rate and reduced conformational changes provides a powerful tool for future studies on the photocycle events that are needed for in vivo signaling by PYP.

Subjects/Keywords: Microbiology

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APA (6^th Edition):

Suresh Rathod, R. R. (2016). Structure-function relationships in the photoactive yellow protein family of photoreceptors. (Thesis). Oklahoma State University. Retrieved from http://pqdtopen.proquest.com/#viewpdf?dispub=10138974

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Suresh Rathod, Rachana Ramila. “Structure-function relationships in the photoactive yellow protein family of photoreceptors.” 2016. Thesis, Oklahoma State University. Accessed April 16, 2021. http://pqdtopen.proquest.com/#viewpdf?dispub=10138974.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Suresh Rathod, Rachana Ramila. “Structure-function relationships in the photoactive yellow protein family of photoreceptors.” 2016. Web. 16 Apr 2021.

Vancouver:

Suresh Rathod RR. Structure-function relationships in the photoactive yellow protein family of photoreceptors. [Internet] [Thesis]. Oklahoma State University; 2016. [cited 2021 Apr 16]. Available from: http://pqdtopen.proquest.com/#viewpdf?dispub=10138974.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Suresh Rathod RR. Structure-function relationships in the photoactive yellow protein family of photoreceptors. [Thesis]. Oklahoma State University; 2016. Available from: http://pqdtopen.proquest.com/#viewpdf?dispub=10138974

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California, San Francisco

4. Moquin, Stephanie. Novel Molecular Insights Into Epstein-Barr Virus Reactivation.

Degree: 2017, University of California, San Francisco

URL: http://pqdtopen.proquest.com/#viewpdf?dispub=10633481

► Epstein-Barr Virus (EBV) is a herpesvirus responsible for approximately 1% of cancers worldwide, including African Burkitt lymphoma, Hodgkin lymphoma, lymphomas in immunosuppressed patients, and… (more)

Subjects/Keywords: Microbiology

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Moquin, S. (2017). Novel Molecular Insights Into Epstein-Barr Virus Reactivation. (Thesis). University of California, San Francisco. Retrieved from http://pqdtopen.proquest.com/#viewpdf?dispub=10633481

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Moquin, Stephanie. “Novel Molecular Insights Into Epstein-Barr Virus Reactivation.” 2017. Thesis, University of California, San Francisco. Accessed April 16, 2021. http://pqdtopen.proquest.com/#viewpdf?dispub=10633481.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Moquin, Stephanie. “Novel Molecular Insights Into Epstein-Barr Virus Reactivation.” 2017. Web. 16 Apr 2021.

Vancouver:

Moquin S. Novel Molecular Insights Into Epstein-Barr Virus Reactivation. [Internet] [Thesis]. University of California, San Francisco; 2017. [cited 2021 Apr 16]. Available from: http://pqdtopen.proquest.com/#viewpdf?dispub=10633481.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Moquin S. Novel Molecular Insights Into Epstein-Barr Virus Reactivation. [Thesis]. University of California, San Francisco; 2017. Available from: http://pqdtopen.proquest.com/#viewpdf?dispub=10633481

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California, Berkeley

5. Berg, Maureen C. Examination of factors that affect the composition and function of the microbiota.

Degree: 2017, University of California, Berkeley

URL: http://pqdtopen.proquest.com/#viewpdf?dispub=10282594

► The microbiota is an important contributor to host health and fitness, impacting all aspects of life, from development and metabolism to immunity and behavior.… (more)

▼ The microbiota is an important contributor to host health and fitness, impacting all aspects of life, from development and metabolism to immunity and behavior. Substantial work has been done to characterize the factors that shape the microbiota, and have demonstrated the importance of both environmental and host factors. However, much of the multifaceted relationship between the environment, the host, and the microbiota remains to be elucidated. My dissertation attempts to demonstrate the ways in which hosts can shape their microbiota through a taxonomic and functional evaluation of microbiotas within two experimental systems. In chapter 1, I examine the relative contributions of the host and the environment to microbiota composition. To characterize the gut microbiota of C. elegans, I used 16S rDNA-targeted sequencing to measure the gut bacteria of worms grown in natural-like environments. By taking advantage of the availability of genetically-homogenous worm populations to reduce noise and average out inter-individual variation, and thus better discern shared features of the C. elegans microbiota, I demonstrate that the worm gut microbiota assembly is a deterministic process. My results suggest a dominant contribution of the host to microbiota composition, and further suggest a role for negative interactions between microbiota members. In chapter 2, I further examined the contribution of host genetics to microbiota composition by identifying differences in microbiotas assembled in worms of different genotypes spanning 200-300 million years of nematode evolution. Using 16S rDNA- targeted sequencing, I demonstrate a significant contribution of host genetics to microbiota composition. However, experimental variables affected worm microbiota composition more than the worm genotype, and hindered my identification of host-specific taxa. In an attempt to overcome this, I isolated members of the Enterobacteriaceae core microbiota family from C. elegans and C. briggsae. This, however, did not identify phylogenetic distinctions between commensals of the two species. In chapter 3, I surveyed the roles of specific host factors in shaping the C. elegans gut microbiota by examining the gut microbiota of C. elegans mutants deficient in feeding and immune function. When selecting mutants, I considered selection during feeding and selection within the intestine as two general ways a host could shape its microbiota. Altered feeding could affect colonization by changes in food choice, food uptake, and food grinding. Immune responses can significantly affect the colonization of pathogens, and it is likely that these immunity and stress response pathways could affect the colonization of non-pathogenic bacteria. In chapter 4, I utilized the tomato plant and P. syringae system to examine the ability of the phyllosphere microbiome to confer resistance to P. syringae infection of tomato leaves. In plants, the phyllosphere (above ground) microbiome is likely to be important for resistance to…

Subjects/Keywords: Microbiology

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Berg, M. C. (2017). Examination of factors that affect the composition and function of the microbiota. (Thesis). University of California, Berkeley. Retrieved from http://pqdtopen.proquest.com/#viewpdf?dispub=10282594

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Berg, Maureen C. “Examination of factors that affect the composition and function of the microbiota.” 2017. Thesis, University of California, Berkeley. Accessed April 16, 2021. http://pqdtopen.proquest.com/#viewpdf?dispub=10282594.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Berg, Maureen C. “Examination of factors that affect the composition and function of the microbiota.” 2017. Web. 16 Apr 2021.

Vancouver:

Berg MC. Examination of factors that affect the composition and function of the microbiota. [Internet] [Thesis]. University of California, Berkeley; 2017. [cited 2021 Apr 16]. Available from: http://pqdtopen.proquest.com/#viewpdf?dispub=10282594.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Berg MC. Examination of factors that affect the composition and function of the microbiota. [Thesis]. University of California, Berkeley; 2017. Available from: http://pqdtopen.proquest.com/#viewpdf?dispub=10282594

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – Berkeley

6. Burch, Adrien Yuan. Biosurfactant Production by Bacteria in the Phyllosphere: Relieving the Tension of Life on a Surface.

Degree: Microbiology, 2011, University of California – Berkeley

URL: http://www.escholarship.org/uc/item/9g6876v9

► Biosurfactants are biologically produced compounds that reduce interfacial tensions due to their water- and oil- loving groups. These amphiphilic substances are widely investigated for their… (more)

▼ Biosurfactants are biologically produced compounds that reduce interfacial tensions due to their water- and oil- loving groups. These amphiphilic substances are widely investigated for their potential commercial exploitation, yet little evidence has been assembled for their direct roles in the environment for the bacteria that produce them. In order to better enable the investigation of biosurfactants, we developed an efficient method for biosurfactant detection that is more sensitive than the standard drop collapse assay, as well as capable of detecting surfactants that have low water solubility and would normally be overlooked. A large number of bacteria recovered from different environments were assessed for biosurfactant production using this atomized oil assay. Detectable biosurfactant production was found to be quite common amongst culturable bacteria, with 5 to 13% of all bacteria from various habitats expressing this trait. Furthermore, we deployed the atomized oil assay in two mutagenesis screens to determine the biosynthetic and regulatory pathways of biosurfactant production in Pseudomonas syringae pv. syringae B728a.A recurring theme that emerges in this dissertation is the importance of biosurfactant production for life on a surface. Not only were biosurfactant-producing bacteria more commonly found in terrestrial surface environments such as leaves than in aqueous samples, but the bacteria that produce biosurfactants were also more likely to produce such compounds when grown on a surface compared to planktonically. Furthermore, the patterns of regulation of the biosurfactants produced by P. syringae also provide additional support for their importance at surfaces. Syringafactin production is higher in cells grown on agar plates than in broth cultures. Also, an unidentified surfactant is produced in larger quantities when P. syringae is grown on hydrated rough surfaces compared to smooth agar plates.Examination of the control of biosurfactant production in P. syringae revealed that syringafactin is regulated by SyfR, a divergently transcribed LuxR-type regulator. SyfR is the mediator of the surface sensing response since in the absence of functional SyfR protein, the SyfR promoter is equally induced in broth and plate cultures, but when present, both the transcription of SyfR and syringafactin is increased on agar plates. A new function for this type of LuxR-type regulator was thus demonstrated. Furthermore, random mutants with altered surfactant production were identified using the atomized oil assay enabling the investigation of biosynthetic and regulatory genes required for the unidentified biosurfactant produced by P. syringae B728a. This surfactant has low water solubility and is synthesized by an acyltransferase that when expressed in trans in E. coli is sufficient for its production. Production of this surfactant is dependent on proper flagellar assembly and the compound was thus…

Subjects/Keywords: Microbiology

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APA (6^th Edition):

Burch, A. Y. (2011). Biosurfactant Production by Bacteria in the Phyllosphere: Relieving the Tension of Life on a Surface. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/9g6876v9

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Burch, Adrien Yuan. “Biosurfactant Production by Bacteria in the Phyllosphere: Relieving the Tension of Life on a Surface.” 2011. Thesis, University of California – Berkeley. Accessed April 16, 2021. http://www.escholarship.org/uc/item/9g6876v9.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Burch, Adrien Yuan. “Biosurfactant Production by Bacteria in the Phyllosphere: Relieving the Tension of Life on a Surface.” 2011. Web. 16 Apr 2021.

Vancouver:

Burch AY. Biosurfactant Production by Bacteria in the Phyllosphere: Relieving the Tension of Life on a Surface. [Internet] [Thesis]. University of California – Berkeley; 2011. [cited 2021 Apr 16]. Available from: http://www.escholarship.org/uc/item/9g6876v9.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Burch AY. Biosurfactant Production by Bacteria in the Phyllosphere: Relieving the Tension of Life on a Surface. [Thesis]. University of California – Berkeley; 2011. Available from: http://www.escholarship.org/uc/item/9g6876v9

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – Irvine

7. Hernandez, Felicia Pilar. Interaction Dynamics of Herpes Simplex Virus Type 1 ICP27 During Infection.

Degree: Biological Sciences, 2010, University of California – Irvine

URL: http://www.escholarship.org/uc/item/8vf92423

► During productive Herpes simplex virus type 1 (HSV-1) infection, the first viral proteins to be expressed are encoded by the immediate-early genes. One of these… (more)

Subjects/Keywords: Microbiology

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APA (6^th Edition):

Hernandez, F. P. (2010). Interaction Dynamics of Herpes Simplex Virus Type 1 ICP27 During Infection. (Thesis). University of California – Irvine. Retrieved from http://www.escholarship.org/uc/item/8vf92423

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Hernandez, Felicia Pilar. “Interaction Dynamics of Herpes Simplex Virus Type 1 ICP27 During Infection.” 2010. Thesis, University of California – Irvine. Accessed April 16, 2021. http://www.escholarship.org/uc/item/8vf92423.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Hernandez, Felicia Pilar. “Interaction Dynamics of Herpes Simplex Virus Type 1 ICP27 During Infection.” 2010. Web. 16 Apr 2021.

Vancouver:

Hernandez FP. Interaction Dynamics of Herpes Simplex Virus Type 1 ICP27 During Infection. [Internet] [Thesis]. University of California – Irvine; 2010. [cited 2021 Apr 16]. Available from: http://www.escholarship.org/uc/item/8vf92423.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Hernandez FP. Interaction Dynamics of Herpes Simplex Virus Type 1 ICP27 During Infection. [Thesis]. University of California – Irvine; 2010. Available from: http://www.escholarship.org/uc/item/8vf92423

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

UCLA

8. Wu, Tingxi. Analysis and Management of Plaques on Intraoral Artificial Dental Materials.

Degree: Oral Biology, 2017, UCLA

URL: http://www.escholarship.org/uc/item/2bb6j7qg

► Oral cavity contains diverse microorganisms including bacteria and fungi. These microbes are able to colonize on natural surfaces, including tooth and mucosa, as well as… (more)

▼ Oral cavity contains diverse microorganisms including bacteria and fungi. These microbes are able to colonize on natural surfaces, including tooth and mucosa, as well as artificial surfaces, such as surfaces of denture, implants, and orthodontic braces. The microbial colonization and formation of biofilms on these biotic and abiotic surfaces may lead to local and systemic diseases such as caries, white spot lesion, gingivitis, halitosis, and denture stomatitis. However, microbial study related to intraoral artificial surfaces has drawn little attention in comparison to microbial study on natural oral surfaces. While I learned my microbiology and molecular biology experimental skills through studying a dental caries related pathogen, Streptococcus mutans, my mian research projects have been focusing on studying plaque on the artificial surfaces and their associations with dental diseases with denture and orthodontic brackets as model systems. In order to study the mechanisms behind these artificial surface plaque associated oral infectious diseases, one would need to first characterize microbial compostion of these plaques as well as establish effective study models, then study the dynamic interactions between different pathogenic species within these plaques. Through understanding the molecular components involved in plaque formation and inter-species interactions, we may develop the tools to manage these diseases. My thesis consists of three parts: Part I describes my initial work of learning microbiology and molecular biology technologies to discover and characterize a novel membrane associated protein (PrsA) in the major cariogenic pathogen, Streptococcus mutans, which is important for cellular aggregation and biofilm formation. In Part II, I applied the molecular biology tools to address clinic relevant issues with a focus on denture related oral microbial diseases, including characterization of the denture associated oral microbiome under healthy and diseased conditions and investigation of the molecular mechanism behind the potential pathogens associated with denture-associated microbial diseases. Part III covers my ongoing studies on orthodontic related oral microbial diseases after I joined orthodontic residency program. In this part, we established a clinical-relevant high-thoughput screening assay to discover compounds that could block orthodontic bracket induced plaque formation, then formulate these biofilm-inhibitory compounds into a toothpaste for the prevention of bracket-induced plaque formation. The clinical efficacy of the toothpaste is being tested now. I also have another ongoing project to characterize the dynamic change of oral microbiomes in orthodontic patients before, during, after orthodontic treatments.

Subjects/Keywords: Microbiology

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APA (6^th Edition):

Wu, T. (2017). Analysis and Management of Plaques on Intraoral Artificial Dental Materials. (Thesis). UCLA. Retrieved from http://www.escholarship.org/uc/item/2bb6j7qg

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Wu, Tingxi. “Analysis and Management of Plaques on Intraoral Artificial Dental Materials.” 2017. Thesis, UCLA. Accessed April 16, 2021. http://www.escholarship.org/uc/item/2bb6j7qg.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Wu, Tingxi. “Analysis and Management of Plaques on Intraoral Artificial Dental Materials.” 2017. Web. 16 Apr 2021.

Vancouver:

Wu T. Analysis and Management of Plaques on Intraoral Artificial Dental Materials. [Internet] [Thesis]. UCLA; 2017. [cited 2021 Apr 16]. Available from: http://www.escholarship.org/uc/item/2bb6j7qg.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Wu T. Analysis and Management of Plaques on Intraoral Artificial Dental Materials. [Thesis]. UCLA; 2017. Available from: http://www.escholarship.org/uc/item/2bb6j7qg

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – San Diego

9. Munguia, Jason. New Approaches to Sensitize Multidrug-Resistant Gram-Negative Bacterial Pathogens to Host Innate Immune Clearance.

Degree: Biomedical Sciences, 2016, University of California – San Diego

URL: http://www.escholarship.org/uc/item/2p92t14d

► Multidrug-resistant Gram-negative (MDRGN) bacterial pathogens pose a significant threat to public health in the US and worldwide. The lack of therapeutic options for MDRGN bacterial… (more)

▼ Multidrug-resistant Gram-negative (MDRGN) bacterial pathogens pose a significant threat to public health in the US and worldwide. The lack of therapeutic options for MDRGN bacterial infection have forced clinicians to use older, once rarely used antibiotics that are associated with significant toxicity. An increasing number of immunocompromised individuals, including the elderly, premature neonates, surgical patients, organ transplant recipients, and those receiving cancer chemotherapy, represent an expanding reservoir for MDRGN bacteria in the hospital setting. Research to understand the molecular host-pathogen interactions involved in MDRGN bacterial infections and reveal novel therapeutic targets are imperative if we are to prevent the advent of a post-antibiotic era. For this PhD dissertation project, I began by searching for genes in the MDRGN bacterial pathogen Acinetobacter baumannii that are important in resisting the bactericidal action of the human cathelicidin antimicrobial peptide, LL-37, a critical front-line effector of host innate defense. A transposon insertion in vacJ, a component of the mla system conserved in all Gram-negative species, proved important in mediating resistance to LL-37, detergents, whole blood, complement, and neutrophils. A. baumannii lacking vacJ demonstrated reduced virulence compared to wild-type parent strain in a murine pneumonia model. To expand the general significance of this work, I examined the virulence capacity of multiple mla mutants in Pseudomonas aeruginosa, a leading MDRGN opportunistic human pathogen. P. aeruginosa lacking an mla system exhibited increased sensitivity to LL-37 and its murine homolog, as well as membrane active pharmaceuticals, serum, and whole blood. A murine pneumonia model revealed reduced bacterial burden and mortality when infected with bacteria lacking vacJ. Finally, I explored how a common antibiotic, azithromycin, traditionally considered ineffective against MDRGN bacteria in standard testing assays, gained entry to its ribosomal target when endogenous antimicrobial peptides modify the outer membrane, allowing it to provide clear efficacy in an in vivo model of A. baumannii pneumonia. Altogether, this dissertation furthered our understanding on the importance outer membrane integrity for Gram-negative bacteria to resist host immune clearance. This research points to a possible therapeutic target in the mla pathway to control MDRGN infections by sensitizing them to the host innate immune system.

Subjects/Keywords: Microbiology

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APA (6^th Edition):

Munguia, J. (2016). New Approaches to Sensitize Multidrug-Resistant Gram-Negative Bacterial Pathogens to Host Innate Immune Clearance. (Thesis). University of California – San Diego. Retrieved from http://www.escholarship.org/uc/item/2p92t14d

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Munguia, Jason. “New Approaches to Sensitize Multidrug-Resistant Gram-Negative Bacterial Pathogens to Host Innate Immune Clearance.” 2016. Thesis, University of California – San Diego. Accessed April 16, 2021. http://www.escholarship.org/uc/item/2p92t14d.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Munguia, Jason. “New Approaches to Sensitize Multidrug-Resistant Gram-Negative Bacterial Pathogens to Host Innate Immune Clearance.” 2016. Web. 16 Apr 2021.

Vancouver:

Munguia J. New Approaches to Sensitize Multidrug-Resistant Gram-Negative Bacterial Pathogens to Host Innate Immune Clearance. [Internet] [Thesis]. University of California – San Diego; 2016. [cited 2021 Apr 16]. Available from: http://www.escholarship.org/uc/item/2p92t14d.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Munguia J. New Approaches to Sensitize Multidrug-Resistant Gram-Negative Bacterial Pathogens to Host Innate Immune Clearance. [Thesis]. University of California – San Diego; 2016. Available from: http://www.escholarship.org/uc/item/2p92t14d

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

10. Park, Jane. Identification and Characterization of Fusobacterial Adhesins Involved in Interspecies Interactions.

Degree: Oral Biology, 2016, UCLA

URL: http://www.escholarship.org/uc/item/611739qf

► Fusobacterium nucleatum is a Gram-negative opportunistic pathogen that is indigenous to the human oral cavity. It is a prevalent member of the oral microbial community… (more)

▼ Fusobacterium nucleatum is a Gram-negative opportunistic pathogen that is indigenous to the human oral cavity. It is a prevalent member of the oral microbial community and considered a key organism in biofilm formation due to its ability to adhere to a large variety of microbial species. While present in healthy oral biofilms, F. nucleatum is also dominant in periodontal disease and has been implicated in a number of invasive human infections, acute and chronic inflammatory conditions as well as adverse pregnancy outcomes. F. nucleatum pathogenicity can be partially attributed to its function as a “bridging organism” that supports the integration of periodontal pathogens into oral biofilms. Despite the extensive exploration of F. nucleatum interspecies interactions and the identification of a number of binding partners, only one fusobacterial large outer membrane protein (OMP), RadD, has been extensively characterized at a molecular level for its role as an adhesin in binding to a variety of Gram-positive species. The identification and characterization of fusobacterial adhesins involved in interspecies interactions addressed in the following aims: (1) We have identified an additional fusobacterial OMP, Fap2, a galactose-inhibitable adhesin that mediates attachment with at least two P. gingivalis strains. We also demonstrate that RadD is an additional strain-specific fusobacterial adhesin for interaction with P. gingivalis and provide evidence that additional adhesins exist that have yet to be identified. (2) An in-depth investigation of the four-gene operon encoding the RadD adhesin revealed that inactivation of the gene directly upstream of radD, named fad-I, resulted in increased binding of F. nucleatum to both Streptococcus gordonii and Porphyromonas gingivalis as a result of the overexpression of radD. The mutant lacking FAD-I also exhibited the enhanced ability to form robust biofilms with S. gordonii. We propose that the protein encoded by fad-I is an element acting as a repressor for radD expression. (3) We also took a global approach to examine contact-induced transcriptional changes that occur when F. nucleatum is in contact with partner species. We report partner-specific responses, suggesting F. nucleatum can differentially regulate its genes based on contact with neighboring species. Furthermore, we report that there are a subset of genes regulated based on the interacting partner and the adhesin mediating attachment.In conclusion, this thesis describes a comprehensive study of fusobacterial adhesins involved in interspecies interactions and further highlights the prominence of F. nucleatum in the oral microbiome warranting future studies that continue to investigate this organism on molecular and “omic” levels.

Subjects/Keywords: Microbiology

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APA (6^th Edition):

Park, J. (2016). Identification and Characterization of Fusobacterial Adhesins Involved in Interspecies Interactions. (Thesis). UCLA. Retrieved from http://www.escholarship.org/uc/item/611739qf

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Park, Jane. “Identification and Characterization of Fusobacterial Adhesins Involved in Interspecies Interactions.” 2016. Thesis, UCLA. Accessed April 16, 2021. http://www.escholarship.org/uc/item/611739qf.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Park, Jane. “Identification and Characterization of Fusobacterial Adhesins Involved in Interspecies Interactions.” 2016. Web. 16 Apr 2021.

Vancouver:

Park J. Identification and Characterization of Fusobacterial Adhesins Involved in Interspecies Interactions. [Internet] [Thesis]. UCLA; 2016. [cited 2021 Apr 16]. Available from: http://www.escholarship.org/uc/item/611739qf.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Park J. Identification and Characterization of Fusobacterial Adhesins Involved in Interspecies Interactions. [Thesis]. UCLA; 2016. Available from: http://www.escholarship.org/uc/item/611739qf

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – San Diego

11. Quach, Diana T. From Antimicrobial Discovery to Clinical Diagnostics: Applications of Bacterial Cytological Profiling.

Degree: Bioengineering, 2016, University of California – San Diego

URL: http://www.escholarship.org/uc/item/06f6n5rc

► The discovery and widespread usage of antibiotics has drastically improved human health in the 20th century. Unfortunately, the extensive use and misuse of antimicrobial drugs… (more)

▼ The discovery and widespread usage of antibiotics has drastically improved human health in the 20th century. Unfortunately, the extensive use and misuse of antimicrobial drugs led to the emergence and spread of drug-resistant pathogens. The threat from increasingly resistant pathogens is exacerbated by the decline in antibacterial drug discovery due to regulatory burden, low profit margins compared to other drugs as well as investments in antibiotic discovery platforms that ultimately proved unproductive. Two approaches aimed at ameliorating this threat include the (1) development of new therapies and antimicrobial agents and (2) implementation of policies to reduce the emergence and spread of resistant pathogens (e.g. using existing antimicrobials more effectively) in a set of strategies known as antimicrobial stewardship. Bacterial cytological profiling (BCP), a microscopy-based technique which creates profiles from the measurement of changes in cellular architecture following antibiotic treatment, contributes to both the discovery of antimicrobials as well as antimicrobial stewardship. BCP had been shown to rapidly identify cellular pathway targeted by antibacterial molecules, thereby demonstrating the utility of BCP in identifying the mode of action (MOA) of unknown compounds in order to prioritize compounds of interest for further development. Here, I show that BCP is a flexible tool that can be applied to study the MOA of antibiotics for Pseudomonas aeruginosa. Additionally, I have developed a rapid, antimicrobial susceptibility test based on BCP (AST-BCP) in order to determine the appropriate antimicrobial therapy in a timely manner thereby reserving antibiotics in the last line of defense for cases which require them. AST-BCP was able to accurately determine the susceptibility profiles for a set of Staphylcoccus aureus clinical isolates and a smaller set of P. aeruginosa strains suggesting that this platform would be appropriate surrogate for traditional susceptibility tests. Finally, I discuss the development of a user-friendly data analysis platform, designed specifically for BCP datasets. The potential application of BCP spans multiple research areas from antimicrobial discovery to resistance identification and is a powerful tool for investigating antimicrobial compounds and clinical pathogens.

Subjects/Keywords: Microbiology

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Quach, D. T. (2016). From Antimicrobial Discovery to Clinical Diagnostics: Applications of Bacterial Cytological Profiling. (Thesis). University of California – San Diego. Retrieved from http://www.escholarship.org/uc/item/06f6n5rc

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Quach, Diana T. “From Antimicrobial Discovery to Clinical Diagnostics: Applications of Bacterial Cytological Profiling.” 2016. Thesis, University of California – San Diego. Accessed April 16, 2021. http://www.escholarship.org/uc/item/06f6n5rc.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Quach, Diana T. “From Antimicrobial Discovery to Clinical Diagnostics: Applications of Bacterial Cytological Profiling.” 2016. Web. 16 Apr 2021.

Vancouver:

Quach DT. From Antimicrobial Discovery to Clinical Diagnostics: Applications of Bacterial Cytological Profiling. [Internet] [Thesis]. University of California – San Diego; 2016. [cited 2021 Apr 16]. Available from: http://www.escholarship.org/uc/item/06f6n5rc.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Quach DT. From Antimicrobial Discovery to Clinical Diagnostics: Applications of Bacterial Cytological Profiling. [Thesis]. University of California – San Diego; 2016. Available from: http://www.escholarship.org/uc/item/06f6n5rc

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – Santa Cruz

12. Collins, Kieran Dennehy. TlpD mediates chemotactic repellent responses to reactive oxygen species that are relevant to Helicobacter pylori gastric gland colonization.

Degree: Microbiology and Environmental Toxicology, 2017, University of California – Santa Cruz

URL: http://www.escholarship.org/uc/item/46f5z88k

► The human gastric pathogen Helicobacter pylori relies upon chemotaxis during early infection, although the system appears dispensable during later stages of infection. This body of… (more)

▼ The human gastric pathogen Helicobacter pylori relies upon chemotaxis during early infection, although the system appears dispensable during later stages of infection. This body of work describes efforts to characterize the signals interpreted by the cytoplasmic chemoreceptor TlpD and gain insight into the role the chemoreceptor plays during infection. Results of this work suggest that TlpD mediates chemotactic repellent responses to stimuli that evoke reactive oxygen species (ROS) formation in the cytoplasm and that these responses are involved in H. pylori colonization of gastric glands. The first chapter serves as a review on chemotactic responses, and focuses on cytoplasmic chemoreceptors. This group of chemoreceptors are understudied relative to their transmembrane counterparts and are prevalent in both bacteria and archaea. An emphasis is placed on describing cytoplasmic chemoreceptors as a group, including likely ligand binding domains and their localization. The ensuing chapters describes basic aspects of TlpD chemotactic responses and their relevance to colonization of the gastric epithelium. TlpD was found to sense and respond to stimuli that provoke cytoplasmic ROS production independently of transmembrane chemoreceptors, which include extracellular iron, hydrogen peroxide and superoxide generators. These findings suggest that the chemoreceptor senses and responds to a yet unknown signal generated by oxidative stress imparted by ROS, which likely involve labile cytoplasmic iron pools. We go on to describe colonization defects of a tlpD mutant, which appears to be connected to gastric gland colonization. The gastric gland colonization defects noted in wild type hosts for a tlpD mutant were rescued in hosts that were deficient in ROS production at the gastric epithelium. These results suggested that TlpD-mediated chemotactic responses to ROS were involved in H. pylori gastric gland colonization, and could be involved in the spread of the bacteria between glands in response to ROS production. Finally we discuss mechanistic issues concerning TlpD recognition of ROS. Taken together these results have bolstered our basic understanding of TlpD signal transduction and the role of the chemoreceptor in host colonization.

Subjects/Keywords: Microbiology

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APA (6^th Edition):

Collins, K. D. (2017). TlpD mediates chemotactic repellent responses to reactive oxygen species that are relevant to Helicobacter pylori gastric gland colonization. (Thesis). University of California – Santa Cruz. Retrieved from http://www.escholarship.org/uc/item/46f5z88k

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Collins, Kieran Dennehy. “TlpD mediates chemotactic repellent responses to reactive oxygen species that are relevant to Helicobacter pylori gastric gland colonization.” 2017. Thesis, University of California – Santa Cruz. Accessed April 16, 2021. http://www.escholarship.org/uc/item/46f5z88k.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Collins, Kieran Dennehy. “TlpD mediates chemotactic repellent responses to reactive oxygen species that are relevant to Helicobacter pylori gastric gland colonization.” 2017. Web. 16 Apr 2021.

Vancouver:

Collins KD. TlpD mediates chemotactic repellent responses to reactive oxygen species that are relevant to Helicobacter pylori gastric gland colonization. [Internet] [Thesis]. University of California – Santa Cruz; 2017. [cited 2021 Apr 16]. Available from: http://www.escholarship.org/uc/item/46f5z88k.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Collins KD. TlpD mediates chemotactic repellent responses to reactive oxygen species that are relevant to Helicobacter pylori gastric gland colonization. [Thesis]. University of California – Santa Cruz; 2017. Available from: http://www.escholarship.org/uc/item/46f5z88k

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – San Diego

13. Baumgart, Leo A. Gene Regulation in Synthetic Biology: Biosensing and Novel Tools for The Construction of Complex Genetic Circuits.

Degree: Biology, 2017, University of California – San Diego

URL: http://www.escholarship.org/uc/item/9cm6x9k9

► One of the pursuits of synthetic biology is to harness gene expression by reprogramming cells to perform useful functions. As one of the most thoroughly… (more)

Subjects/Keywords: Microbiology

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Baumgart, L. A. (2017). Gene Regulation in Synthetic Biology: Biosensing and Novel Tools for The Construction of Complex Genetic Circuits. (Thesis). University of California – San Diego. Retrieved from http://www.escholarship.org/uc/item/9cm6x9k9

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Baumgart, Leo A. “Gene Regulation in Synthetic Biology: Biosensing and Novel Tools for The Construction of Complex Genetic Circuits.” 2017. Thesis, University of California – San Diego. Accessed April 16, 2021. http://www.escholarship.org/uc/item/9cm6x9k9.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Baumgart, Leo A. “Gene Regulation in Synthetic Biology: Biosensing and Novel Tools for The Construction of Complex Genetic Circuits.” 2017. Web. 16 Apr 2021.

Vancouver:

Baumgart LA. Gene Regulation in Synthetic Biology: Biosensing and Novel Tools for The Construction of Complex Genetic Circuits. [Internet] [Thesis]. University of California – San Diego; 2017. [cited 2021 Apr 16]. Available from: http://www.escholarship.org/uc/item/9cm6x9k9.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Baumgart LA. Gene Regulation in Synthetic Biology: Biosensing and Novel Tools for The Construction of Complex Genetic Circuits. [Thesis]. University of California – San Diego; 2017. Available from: http://www.escholarship.org/uc/item/9cm6x9k9

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

UCLA

14. Wu, Michelle. A phylogenetic study of Fusobacterium nucleatum using the major outer membrane protein FomA.

Degree: Oral Biology, 2014, UCLA

URL: http://www.escholarship.org/uc/item/6td360t5

► Taxonomic studies using rRNA and protein coding genes as molecular markers have been used to study the heterogeneity of Fusobacterium nucleatum. Efforts have been made… (more)

▼ Taxonomic studies using rRNA and protein coding genes as molecular markers have been used to study the heterogeneity of Fusobacterium nucleatum. Efforts have been made to determine differences between fusobacterial strains and prevalence of subspecies in sites of health or disease, but a conclusive correlation between the different subspecies and virulence factors still has not been found. Previously used molecular markers have been internal, cytoplasmic markers. However, when looking at strains and subspecies involved in disease, it is important to look at virulence factors, which are often external markers. In this study, we chose the major outer membrane protein FomA of Fusobacterium nucleatum as a phylogenetic molecular marker because of its suggested role in virulence. To determine the fomA gene's utility as a phylogenetic molecular marker, the fomA gene was amplified in 24 strains of Fusobacterium. The corresponding nucleotide sequences and deduced FomA amino acid sequences were used to create alignments and phylogenetic trees for analysis of Fusobacterium subspecies. It was found that the resulting clade distribution does not follow the subspecies clade distribution determined previously by using internal molecular markers such as 16S rRNA and gyrB. The variability from the FomA surface-exposed loops within and between subspecies is responsible for the clade distribution of the strains, and there is no correlation between clade distribution and body site of strain isolation. It is suggested that variable regions could account for the specificity of binding to other species and targets that F. nucleatum experiences, and its affect on virulence, and the functions of each strain may be dictated by the composition of the FomA surface exposed loops, versus the actual subspecies. Therefore, FomA may not be a relevant phylogenetic molecular marker for F. nucleatum subspecies classification, but it may be reflective of functional relationships in strains of F. nucleatum.

Subjects/Keywords: Microbiology

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Wu, M. (2014). A phylogenetic study of Fusobacterium nucleatum using the major outer membrane protein FomA. (Thesis). UCLA. Retrieved from http://www.escholarship.org/uc/item/6td360t5

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Wu, Michelle. “A phylogenetic study of Fusobacterium nucleatum using the major outer membrane protein FomA.” 2014. Thesis, UCLA. Accessed April 16, 2021. http://www.escholarship.org/uc/item/6td360t5.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Wu, Michelle. “A phylogenetic study of Fusobacterium nucleatum using the major outer membrane protein FomA.” 2014. Web. 16 Apr 2021.

Vancouver:

Wu M. A phylogenetic study of Fusobacterium nucleatum using the major outer membrane protein FomA. [Internet] [Thesis]. UCLA; 2014. [cited 2021 Apr 16]. Available from: http://www.escholarship.org/uc/item/6td360t5.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Wu M. A phylogenetic study of Fusobacterium nucleatum using the major outer membrane protein FomA. [Thesis]. UCLA; 2014. Available from: http://www.escholarship.org/uc/item/6td360t5

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

UCLA

15. Chang, Michaela. A Comparative Community Analysis of the Periodontitis Microbiome.

Degree: Oral Biology, 2012, UCLA

URL: http://www.escholarship.org/uc/item/6sj6k714

► Metagenomics using high-throughput DNA sequencing technologies is becoming a common approach for microbial community characterization. However, not many studies have compared the traditional 16S rRNA… (more)

▼ Metagenomics using high-throughput DNA sequencing technologies is becoming a common approach for microbial community characterization. However, not many studies have compared the traditional 16S rRNA clone library approach with the new metagenomic approaches. In this study, we analyzed the community structure of the subgingival microbiome of periodontitis before and after initial therapy. Two approaches were employed in parallel - metagenomic shotgun sequencing and the traditional 16S rRNA clone library method using Sanger sequencing. This allowed us to compare the two approaches. DNA was extracted from subgingival plaque samples obtained from sites with chronic periodontitis in four systemically healthy subjects prior to and 4-6 weeks following initial therapy. For metagenomics sequencing, 100 bp paired-end reads were generated using Illumina sequencing platforms. Two analysis methods were used in analyzing the metagenomic sequencing data. First, the 16S rRNA reads were extracted and aligned against SILVA rRNA database for taxonomic assignment. Second, the metagenomic reads were mapped against a database of microbial reference genomes for genome identification. For clone library analysis, the 16S rRNA gene was amplified and cloned. Plasmid inserts were sequenced bidirectionally and the taxa were assigned using the Microbiome Utilities Portal of Broad Institute. Statistical evaluation of the results demonstrated that the two sequencing approaches revealed consistent microbial community structure of the oral microbiome. The three analysis methods based on the metagenomic sequencing data and clone library data uncovered the presence of a diverse bacterial community in the subgingiva of periodontitis with little detection bias of the major oral microorganisms. The three analyses demonstrated consistent overall decreases in Porphyromonas, Neisseria and Treponema, and increases in Fusobacterium, Veillonella, Prevotella and Streptococcus after treatment. We observed microbial community shift from disease to resolution of periodontitis at genus level, which could allow the use of a few microbial markers in periodontitis diagnosis and monitoring.

Subjects/Keywords: Microbiology

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Chang, M. (2012). A Comparative Community Analysis of the Periodontitis Microbiome. (Thesis). UCLA. Retrieved from http://www.escholarship.org/uc/item/6sj6k714

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Chang, Michaela. “A Comparative Community Analysis of the Periodontitis Microbiome.” 2012. Thesis, UCLA. Accessed April 16, 2021. http://www.escholarship.org/uc/item/6sj6k714.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Chang, Michaela. “A Comparative Community Analysis of the Periodontitis Microbiome.” 2012. Web. 16 Apr 2021.

Vancouver:

Chang M. A Comparative Community Analysis of the Periodontitis Microbiome. [Internet] [Thesis]. UCLA; 2012. [cited 2021 Apr 16]. Available from: http://www.escholarship.org/uc/item/6sj6k714.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Chang M. A Comparative Community Analysis of the Periodontitis Microbiome. [Thesis]. UCLA; 2012. Available from: http://www.escholarship.org/uc/item/6sj6k714

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

UCLA

16. Chikere, Kelechi C. Quantitative and high-throughput receptor affinity profiling system reveals distinct pathophysiological HIV-1 phenotypes.

Degree: Microbiology, Immunology, & Molecular Genetics, 2012, UCLA

URL: http://www.escholarship.org/uc/item/8jk096v8

► HIV-1 affinity for CD4 and CCR5 is associated with differential pathogenicity. Therefore, we pioneered a dually inducible cell line based system that could quantitatively and… (more)

▼ HIV-1 affinity for CD4 and CCR5 is associated with differential pathogenicity. Therefore, we pioneered a dually inducible cell line based system that could quantitatively and comprehensively characterize viral entry efficiency as a co-dependent function of CD4 and CCR5 expression levels. This receptor affinity profiling system (Affinofile) has revealed biologically relevant phenotypes in Envelopes (Envs) with differential CD4/CCR5 usage efficiencies, providing a more refined understanding of receptor and coreceptor affinities, which can have an impact on the development and use of HIV-1 therapeutics.To facilitate a more rapid and refined analysis of CD4 and CCR5 usage efficiencies with even greater sensitivity, we engineered a reporter Affinofile system containing a tat-rev dependent eGFP-Gaussia luciferase Reporter (GGR). Using this GGR Affinofile system, we (1) characterized the phenotypic and biological consequences for Envs with defined mutations that modulate CD4 or CCR5 binding, (2) determined Transmitter/Founder (T/F) Envs have differential CD4/CCR5 usage compared to Chronic Env, (3) revealed phenotypically distinct CD4/CCR5 usage patterns among the prevalent HIV-1 subtypes (A,B, C and D), and (4) uncovered that mutations that confer resistance to Broadly Neutralizing Antibodies (BNAbs) often compromised the efficiency of CD4/CCR5 usage and entry. Analysis of mutations known to only modulate CCR5 (K421D, S142N) binding demonstrated that CD4 and CCR5 usage is an inter-related process as mutations that affect CD4 binding influenced the efficiency of CCR5 usage and vice versa. The relative entry efficiencies defined in GGR Affinofile system were also reflected in their entry efficiencies into primary CD4+ T cell subsets. In addition, we show that transmitter/founder and chronic envelopes have distinct entry efficiencies that yield characteristic vector metrics. Next, we analyzed over 28 pseudotyped HIV-1 viruses from four different subtypes, and noted that subtype C envelopes could be distinguished from the other subtypes based on their greater efficiency of CD4/CCR5 usage which was reflected in their vector metrics (increased vector angle and mean infectivity). Lastly, envelopes with engineered mutations known to confer resistance to BNAbs, VRC01 and PG6/PG19, invariably resulted in a decreased CD4/CCR5 usage efficiency.Our results suggest that our GGR Affinofile system can quantify and reveal biologically relevant differences in CD4/CCR5 usage patterns in Envs that reflect their genetic-epidemiological differences, pathogenicity, cell tropism, and even fitness cost as a result of resistant-mutations to BNAbs.

Subjects/Keywords: Microbiology

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Chikere, K. C. (2012). Quantitative and high-throughput receptor affinity profiling system reveals distinct pathophysiological HIV-1 phenotypes. (Thesis). UCLA. Retrieved from http://www.escholarship.org/uc/item/8jk096v8

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Chikere, Kelechi C. “Quantitative and high-throughput receptor affinity profiling system reveals distinct pathophysiological HIV-1 phenotypes.” 2012. Thesis, UCLA. Accessed April 16, 2021. http://www.escholarship.org/uc/item/8jk096v8.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Chikere, Kelechi C. “Quantitative and high-throughput receptor affinity profiling system reveals distinct pathophysiological HIV-1 phenotypes.” 2012. Web. 16 Apr 2021.

Vancouver:

Chikere KC. Quantitative and high-throughput receptor affinity profiling system reveals distinct pathophysiological HIV-1 phenotypes. [Internet] [Thesis]. UCLA; 2012. [cited 2021 Apr 16]. Available from: http://www.escholarship.org/uc/item/8jk096v8.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Chikere KC. Quantitative and high-throughput receptor affinity profiling system reveals distinct pathophysiological HIV-1 phenotypes. [Thesis]. UCLA; 2012. Available from: http://www.escholarship.org/uc/item/8jk096v8

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – San Diego

17. Busch, Julia. The diversity, distribution, and biological activity of brominated natural products in the genus Pseudoalteromonas.

Degree: Scripps Institution of Oceanography, 2018, University of California – San Diego

URL: http://www.escholarship.org/uc/item/78t2h9kt

► Secondary metabolite production plays an important role in the interaction of bacteria and their environments. While many marine microbes have been found to produce bioactive… (more)

▼ Secondary metabolite production plays an important role in the interaction of bacteria and their environments. While many marine microbes have been found to produce bioactive molecules, relatively little is known about the diversity and distribution of biosynthetic gene clusters with known products. This dissertation includes five chapters that explore these topics in the genus Pseudoalteromonas. The first chapter introduces marine natural products and the group of bacteria, followed by three research chapters and a summary chapter. Chapter 2 explores the evolution of the bmp gene cluster in the genus Pseudoalteromonas. A well-supported species phylogeny was generated and the distribution and diversity of the biosynthetic gene cluster was mapped onto the tree. Four distinct versions of the bmp cluster were found in the genus, with evidence supporting gene loss in certain cases. It is uncertain how many times the gene cluster was acquired within Pseudoalteromonas, but the conservation of the biosynthetic genes within some lineages suggests that the metabolites produced are relevant to the ecology of these bacteria. Chapter 3 presents the results from the bacterial cytological profiling of pentabromopseudilin in an E. coli strain. The primary phenotype observed in treated cells was membrane permeability, which increases over time and concentration. Despite its apparent ability to disrupt the cell membrane of Gram-negative bacteria and increase the potency of two tested antibiotics, pentabromopseudilin is not likely a good candidate for therapeutic uses due its cytotoxicity. The final research chapter investigates the bioactivity and biosynthetic potential of five Pseudoalteromonas species. The crude extracts and fractions of some of the strains included in the study were bioactive against Gram-positive and Gram-negative test strains. Preliminary genome mining results reveal that Pseudoalteromonas are rich in biosynthetic gene clusters, most of which do not have known products or similar clusters.

Subjects/Keywords: Microbiology

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APA (6^th Edition):

Busch, J. (2018). The diversity, distribution, and biological activity of brominated natural products in the genus Pseudoalteromonas. (Thesis). University of California – San Diego. Retrieved from http://www.escholarship.org/uc/item/78t2h9kt

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Busch, Julia. “The diversity, distribution, and biological activity of brominated natural products in the genus Pseudoalteromonas.” 2018. Thesis, University of California – San Diego. Accessed April 16, 2021. http://www.escholarship.org/uc/item/78t2h9kt.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Busch, Julia. “The diversity, distribution, and biological activity of brominated natural products in the genus Pseudoalteromonas.” 2018. Web. 16 Apr 2021.

Vancouver:

Busch J. The diversity, distribution, and biological activity of brominated natural products in the genus Pseudoalteromonas. [Internet] [Thesis]. University of California – San Diego; 2018. [cited 2021 Apr 16]. Available from: http://www.escholarship.org/uc/item/78t2h9kt.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Busch J. The diversity, distribution, and biological activity of brominated natural products in the genus Pseudoalteromonas. [Thesis]. University of California – San Diego; 2018. Available from: http://www.escholarship.org/uc/item/78t2h9kt

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – San Diego

18. Tuttle, Robert. The chemical ecology of marine bacteria and the sediments they inhabit.

Degree: Scripps Institution of Oceanography, 2018, University of California – San Diego

URL: http://www.escholarship.org/uc/item/7594396g

► Since the first studies looking into how plant specialized metabolites provide defense from herbivory, the field of chemical ecology has explored how organisms interact within… (more)

▼ Since the first studies looking into how plant specialized metabolites provide defense from herbivory, the field of chemical ecology has explored how organisms interact within their environment, and how these interactions structure the ecosystem. Over the last century, we have come to understand a lot about chemical signaling in plants and animals, but our understanding of bacterial chemical signaling is still in its infancy. This is partially because most of the focus has been placed on understanding bacteria potential for drug development as opposed to understanding their ecological roles. This thesis consists of five chapters and explores the interplay between bacterial specialized metabolites in marine sediments, their producers, and their ecological roles, by focusing on the model marine bacterial genus Salinispora. What follows are three research chapters preceded by an introduction to chemical ecology. The introduction focuses on our current understanding of marine bacterial chemical ecology, followed by a brief description of cutting edge mass spectrometry techniques that are now being exploited to further our understanding of the chemical landscape in the environment. Chapter 2 summarizes a study concerning the identification of specialized metabolites in situ and the correlation between these metabolites and their potential producers. Heterotrophic marine sediment bacteria are prolific producers of natural products, but surprisingly little is known about the compounds they produce in the environment and their effects on co-occurring microbes. Using mass spectrometry and molecular networking, characterization of the sediment metabolome was undertaken from Belizean reef habitats. Dereplication results revealed numerous compounds could be detected directly from the sediments including synthetic, sponge, algal, and bacterial metabolites. Interestingly, one of these compounds, the cytotoxin staurosporine, was further quantified and found to occur in the sediments at abundances higher than those established to inhibit protein kinases as well as marine organisms. A 16S rRNA community analysis as well as culturing helped correlate the production of staurosporine to the obligate marine actinomycete species Salinispora arenicola. These results indicate that microbial organisms are likely capable of producing cytotoxins in situ at appreciable quantities that likely impact the community structure of the sediment biome. Since the cytotoxin staurosporine, which is produced by Salinispora, was found to be abundant in the sediments, chapter 3 explored the potential for Salinispora to deter predatory eukaryotic organisms. S. arenicola and S. tropica co-occur in the Caribbean and share greater than 99% 16s rRNA. A recent sequencing effort revealed that each species maintains a unique set BGCs, with S. arenicola containing the BGC to produce staurosporine and S. tropica the BGCs to produce lomaiviticins, and salinosporamides. Numerous assays were developed to assess the ability of Salinispora spp. to deter feeding by the…

Subjects/Keywords: Microbiology

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APA (6^th Edition):

Tuttle, R. (2018). The chemical ecology of marine bacteria and the sediments they inhabit. (Thesis). University of California – San Diego. Retrieved from http://www.escholarship.org/uc/item/7594396g

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Tuttle, Robert. “The chemical ecology of marine bacteria and the sediments they inhabit.” 2018. Thesis, University of California – San Diego. Accessed April 16, 2021. http://www.escholarship.org/uc/item/7594396g.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Tuttle, Robert. “The chemical ecology of marine bacteria and the sediments they inhabit.” 2018. Web. 16 Apr 2021.

Vancouver:

Tuttle R. The chemical ecology of marine bacteria and the sediments they inhabit. [Internet] [Thesis]. University of California – San Diego; 2018. [cited 2021 Apr 16]. Available from: http://www.escholarship.org/uc/item/7594396g.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Tuttle R. The chemical ecology of marine bacteria and the sediments they inhabit. [Thesis]. University of California – San Diego; 2018. Available from: http://www.escholarship.org/uc/item/7594396g

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

19. Shirreff, Lisa M. Characterization of an M. marinum Vaccine| Examination of Both Mucosal Immunity and Systemic Immunity in a Fish Model.

Degree: 2016, University of Louisiana at Lafayette

URL: http://pqdtopen.proquest.com/#viewpdf?dispub=10163372

► Mycobacterium marinum (Mm) shares at least 80% amino acid sequence identity with over 3,000 orthologous genes of Mycobacterium tuberculosis (Mtb) and is thus used… (more)

▼ Mycobacterium marinum (Mm) shares at least 80% amino acid sequence identity with over 3,000 orthologous genes of Mycobacterium tuberculosis (Mtb) and is thus used as a surrogate pathogen for Mtb research. Our laboratory investigates mycobacteriosis using Japanese medaka ( Oryzias latipes) as an aquatic animal model. Mm disease presentation in medaka is similar to Mtb disease presentation in humans, including growth in macrophages, granulomatous lesions, and lifelong chronic disease. We have previously shown that a major route of infection in fish is through an oral route and have thus developed methods to infect medaka with Mm utilizing mosquito larvae as vectors. Recently, our lab was able to show that Mm is able to cross the gut epithelia of medaka in a relatively short-time frame and travel to the underlying submucosa. Therefore, Mm must have the ability to attach to the gut mucosal layer and evade killing by GALT immune cells. Mm is apparently able to exploit macrophages of the mucosal immune system to transport the bacteria to target organs like the head kidney, liver, and spleen for a systemic infection. Utilizing an Mm strain engineered to carry a deletion in the RD-1 region, known to include a number of virulence genes, our lab has shown that mucosal immunity against Mm can be induced in medaka. We have shown that exposure to the mutant RD-1 strain offers some protection against a chronic wild-type oral challenge. Since we know that mutant RD-1 can elicit a mucosal immune response, I tested to see if sensitizing mucosal immunity would also induce systemic immunity by first priming fish with mutant RD-1 and then subsequently challenging them with wild type Mm via an IP route. This thesis demonstrates that mucosal immunity is limited to the gut and thus does not appear to provide broad systemic immunity. Additionally, I tested to see if systemic vaccination would protect against a systemic virulent wild-type challenge by vaccinating and challenging fish via an IP route of infection. Results showed that systemic vaccination does not induce systemic immunity and thus does not protect against an IP injected virulent challenge. Collectively, results from this thesis have shown mutant RD-1 to only be effective as a vaccine against mycobacteriosis if given orally since it was shown to only induce a mucosal immune response and only be protective against an oral virulent wild type challenge.

Subjects/Keywords: Microbiology

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APA (6^th Edition):

Shirreff, L. M. (2016). Characterization of an M. marinum Vaccine| Examination of Both Mucosal Immunity and Systemic Immunity in a Fish Model. (Thesis). University of Louisiana at Lafayette. Retrieved from http://pqdtopen.proquest.com/#viewpdf?dispub=10163372

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Shirreff, Lisa M. “Characterization of an M. marinum Vaccine| Examination of Both Mucosal Immunity and Systemic Immunity in a Fish Model.” 2016. Thesis, University of Louisiana at Lafayette. Accessed April 16, 2021. http://pqdtopen.proquest.com/#viewpdf?dispub=10163372.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Shirreff, Lisa M. “Characterization of an M. marinum Vaccine| Examination of Both Mucosal Immunity and Systemic Immunity in a Fish Model.” 2016. Web. 16 Apr 2021.

Vancouver:

Shirreff LM. Characterization of an M. marinum Vaccine| Examination of Both Mucosal Immunity and Systemic Immunity in a Fish Model. [Internet] [Thesis]. University of Louisiana at Lafayette; 2016. [cited 2021 Apr 16]. Available from: http://pqdtopen.proquest.com/#viewpdf?dispub=10163372.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Shirreff LM. Characterization of an M. marinum Vaccine| Examination of Both Mucosal Immunity and Systemic Immunity in a Fish Model. [Thesis]. University of Louisiana at Lafayette; 2016. Available from: http://pqdtopen.proquest.com/#viewpdf?dispub=10163372

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – Berkeley

20. De Leon, Justin A. Mixed Signals: Regulation of host metabolism by an intracellular bacterial pathogen.

Degree: Molecular & Cell Biology, 2017, University of California – Berkeley

URL: http://www.escholarship.org/uc/item/24r5832m

► A hallmark of all pathogens is an ability to acquire nutrients from hosts. In order to do this, pathogens must overcome both the tight regulation… (more)

Subjects/Keywords: Microbiology

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APA (6^th Edition):

De Leon, J. A. (2017). Mixed Signals: Regulation of host metabolism by an intracellular bacterial pathogen. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/24r5832m

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

De Leon, Justin A. “Mixed Signals: Regulation of host metabolism by an intracellular bacterial pathogen.” 2017. Thesis, University of California – Berkeley. Accessed April 16, 2021. http://www.escholarship.org/uc/item/24r5832m.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

De Leon, Justin A. “Mixed Signals: Regulation of host metabolism by an intracellular bacterial pathogen.” 2017. Web. 16 Apr 2021.

Vancouver:

De Leon JA. Mixed Signals: Regulation of host metabolism by an intracellular bacterial pathogen. [Internet] [Thesis]. University of California – Berkeley; 2017. [cited 2021 Apr 16]. Available from: http://www.escholarship.org/uc/item/24r5832m.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

De Leon JA. Mixed Signals: Regulation of host metabolism by an intracellular bacterial pathogen. [Thesis]. University of California – Berkeley; 2017. Available from: http://www.escholarship.org/uc/item/24r5832m

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

George Mason University

21. Propst, Crystal. Lung-Directed Delivery of Therapeutics for the Treatment of Pulmonary Francisella Infection .

Degree: 2015, George Mason University

URL: http://hdl.handle.net/1920/9892

► According to the World Lung Foundation, acute respiratory infections result in 4.25 million deaths each year, are the third largest cause of mortality worldwide, and… (more)

Subjects/Keywords: Microbiology

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APA (6^th Edition):

Propst, C. (2015). Lung-Directed Delivery of Therapeutics for the Treatment of Pulmonary Francisella Infection . (Thesis). George Mason University. Retrieved from http://hdl.handle.net/1920/9892

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Propst, Crystal. “Lung-Directed Delivery of Therapeutics for the Treatment of Pulmonary Francisella Infection .” 2015. Thesis, George Mason University. Accessed April 16, 2021. http://hdl.handle.net/1920/9892.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Propst, Crystal. “Lung-Directed Delivery of Therapeutics for the Treatment of Pulmonary Francisella Infection .” 2015. Web. 16 Apr 2021.

Vancouver:

Propst C. Lung-Directed Delivery of Therapeutics for the Treatment of Pulmonary Francisella Infection . [Internet] [Thesis]. George Mason University; 2015. [cited 2021 Apr 16]. Available from: http://hdl.handle.net/1920/9892.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Propst C. Lung-Directed Delivery of Therapeutics for the Treatment of Pulmonary Francisella Infection . [Thesis]. George Mason University; 2015. Available from: http://hdl.handle.net/1920/9892

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Loyola University Chicago

22. Hu, Linda. Understanding the Posttranslational Regulation of the Response Regulator Rcsb and Acetyl Phosphate as an Acetyl Group Donor in E. Coli.

Degree: PhD, Microbiology and Immunology, 2013, Loyola University Chicago

URL: https://ecommons.luc.edu/luc_diss/722

► The observation that Nepsilon-lysine acetylation occurs on a hundreds of proteins in bacteria is a recent discovery. To study the mechanisms that regulate acetylation… (more)

Subjects/Keywords: Microbiology

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APA (6^th Edition):

Hu, L. (2013). Understanding the Posttranslational Regulation of the Response Regulator Rcsb and Acetyl Phosphate as an Acetyl Group Donor in E. Coli. (Doctoral Dissertation). Loyola University Chicago. Retrieved from https://ecommons.luc.edu/luc_diss/722

Chicago Manual of Style (16^th Edition):

Hu, Linda. “Understanding the Posttranslational Regulation of the Response Regulator Rcsb and Acetyl Phosphate as an Acetyl Group Donor in E. Coli.” 2013. Doctoral Dissertation, Loyola University Chicago. Accessed April 16, 2021. https://ecommons.luc.edu/luc_diss/722.

MLA Handbook (7^th Edition):

Hu, Linda. “Understanding the Posttranslational Regulation of the Response Regulator Rcsb and Acetyl Phosphate as an Acetyl Group Donor in E. Coli.” 2013. Web. 16 Apr 2021.

Vancouver:

Hu L. Understanding the Posttranslational Regulation of the Response Regulator Rcsb and Acetyl Phosphate as an Acetyl Group Donor in E. Coli. [Internet] [Doctoral dissertation]. Loyola University Chicago; 2013. [cited 2021 Apr 16]. Available from: https://ecommons.luc.edu/luc_diss/722.

Council of Science Editors:

Hu L. Understanding the Posttranslational Regulation of the Response Regulator Rcsb and Acetyl Phosphate as an Acetyl Group Donor in E. Coli. [Doctoral Dissertation]. Loyola University Chicago; 2013. Available from: https://ecommons.luc.edu/luc_diss/722

Loyola University Chicago

23. Ashraf, Asiyya. A Possible Role of Clostridium Difficile Association With the GI Tract in Relapsing Clostridium Difficile Infection.

Degree: MS, Microbiology and Immunology, 2019, Loyola University Chicago

URL: https://ecommons.luc.edu/luc_theses/3980

► Clostridium difficile infection (CDI), caused by the anaerobic spore-former C. difficile, is a major cause of health-care associated morbidity. CDI occurs in individuals that have… (more)

Subjects/Keywords: Microbiology

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APA (6^th Edition):

Ashraf, A. (2019). A Possible Role of Clostridium Difficile Association With the GI Tract in Relapsing Clostridium Difficile Infection. (Thesis). Loyola University Chicago. Retrieved from https://ecommons.luc.edu/luc_theses/3980

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ashraf, Asiyya. “A Possible Role of Clostridium Difficile Association With the GI Tract in Relapsing Clostridium Difficile Infection.” 2019. Thesis, Loyola University Chicago. Accessed April 16, 2021. https://ecommons.luc.edu/luc_theses/3980.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ashraf, Asiyya. “A Possible Role of Clostridium Difficile Association With the GI Tract in Relapsing Clostridium Difficile Infection.” 2019. Web. 16 Apr 2021.

Vancouver:

Ashraf A. A Possible Role of Clostridium Difficile Association With the GI Tract in Relapsing Clostridium Difficile Infection. [Internet] [Thesis]. Loyola University Chicago; 2019. [cited 2021 Apr 16]. Available from: https://ecommons.luc.edu/luc_theses/3980.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ashraf A. A Possible Role of Clostridium Difficile Association With the GI Tract in Relapsing Clostridium Difficile Infection. [Thesis]. Loyola University Chicago; 2019. Available from: https://ecommons.luc.edu/luc_theses/3980

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of KwaZulu-Natal

24. Tredgold, Heather Rayne. Screening for aerobic endospore-forming bacteria as biocontrol agents for powdery mildew disease of cucurbits.

Degree: 2015, University of KwaZulu-Natal

URL: http://hdl.handle.net/10413/13937

► Powdery mildew of cucurbits costs the South African cucurbit-growing industry millions of Rands per year in reduced yields and compromised fruit quality. Amongst the many… (more)

▼ Powdery mildew of cucurbits costs the South African cucurbit-growing industry millions of Rands per year in reduced yields and compromised fruit quality. Amongst the many bacterial and fungal antagonists of cucurbit powdery mildew, certain aerobic endospore-forming bacteria (AEFB) species show promise as biocontrol agents of this disease. When embarking upon biocontrol agent selection, multifaceted screening strategies are crucial. A study was undertaken with the aim of isolating AEFB from the cucurbit phylloplane for evaluation as potential antagonists of cucurbit powdery mildew using various screening approaches. Three hundred and nine AEFB isolates were isolated from cucurbit leaf material sourced from eight locations in the greater Msunduzi, KZN region. Dual-culture antifungal bioassays were performed using surrogate phytopathogenic fungi Botrytis cinerea and Rhizoctonia solani in place of the obligately biotrophic Podosphaera spp.. Two PCR-based genotyping methods were used to differentiate and group 55 antifungal AEFB isolates: internal-transcribed spacer region (ITS) PCR and randomly amplified polymorphic DNA (RAPD) PCR. The RAPD-PCR distinguished greater levels of genetic polymorphisms amongst isolates than did the ITS-PCR, revealing 14 different profiles as opposed to the three obtained from ITS-PCR; with 42% of isolates associated with a single RAPD-PCR banding profile. Phylogenetic relationships between representatives of each of the RAPD-PCR fingerprint groupings were determined by sequence analysis of 16S rRNA and gyrase subunit A (gyrA) gene fragments. In each instance, several distinct clusters were discernable, though gyrA sequences displayed higher levels of strain-level sequence heterogeneity. Comparisons of both gene sequence types with reference strains from the GenBank database revealed similarities to several known plant-associated strains of AEFB, including B. amyloliquefaciens subsp. plantarum and B. subtilis. Matrix-assisted laser deionisation-desorption time-of-flight mass spectrometry (MALDI-TOF-MS) based identification of selected AEFB was evaluated by comparing spectral data from AEFB isolates with reference strains in a Bruker BDAL Biotyper database. Only three out of the 14 isolates evaluated were identified to species level with acceptable confidence levels. This poor taxonomic resolution was ascribed to a paucity of applicable reference strains in the BDAL library. Nevertheless, mass spectra profiles of each isolate allowed for the clustering of related isolates to be achieved when dendograms were created. Antifungal compounds were extracted from 14 isolates using an acid-precipitation and methanol extraction protocol. Detection and identification of lipopeptide compounds in these extracts was assessed using thin-layer chromatography (TLC) and MALDI-TOF-MS. PCR-based screening for lipopeptide production potential using selected lipopeptide gene markers (viz. surfactin, iturin, bacillomycin, and fengycin) was also evaluated for the selected 14 isolates. These isolates were found to… Advisors/Committee Members: Hunter, Charles Haig. (advisor).

Subjects/Keywords: Microbiology

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APA (6^th Edition):

Tredgold, H. R. (2015). Screening for aerobic endospore-forming bacteria as biocontrol agents for powdery mildew disease of cucurbits. (Thesis). University of KwaZulu-Natal. Retrieved from http://hdl.handle.net/10413/13937

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Tredgold, Heather Rayne. “Screening for aerobic endospore-forming bacteria as biocontrol agents for powdery mildew disease of cucurbits.” 2015. Thesis, University of KwaZulu-Natal. Accessed April 16, 2021. http://hdl.handle.net/10413/13937.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Tredgold, Heather Rayne. “Screening for aerobic endospore-forming bacteria as biocontrol agents for powdery mildew disease of cucurbits.” 2015. Web. 16 Apr 2021.

Vancouver:

Tredgold HR. Screening for aerobic endospore-forming bacteria as biocontrol agents for powdery mildew disease of cucurbits. [Internet] [Thesis]. University of KwaZulu-Natal; 2015. [cited 2021 Apr 16]. Available from: http://hdl.handle.net/10413/13937.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Tredgold HR. Screening for aerobic endospore-forming bacteria as biocontrol agents for powdery mildew disease of cucurbits. [Thesis]. University of KwaZulu-Natal; 2015. Available from: http://hdl.handle.net/10413/13937

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of KwaZulu-Natal

25. Musoke, Jolly. Investigation into the diversity of antifungal aerobic endospore-forming bacteria associated with bulk and crop rhizosphere soil.

Degree: MS, Microbiology, 2011, University of KwaZulu-Natal

URL: http://hdl.handle.net/10413/8057

► Members of the genus Bacillus are mainly Gram positive, aerobic rod shaped, endospore-forming bacteria that are increasingly being recognised for their ability to promote plant… (more)

▼ Members of the genus Bacillus are mainly Gram positive, aerobic rod shaped, endospore-forming bacteria that are increasingly being recognised for their ability to promote plant growth and antagonise fungal pathogens. From a biological control perspective, Bacillus spp. strains that produce antifungal compounds are of particular interest. In this study, aerobic endospore-formers were isolated from an undisturbed indigenous grassland soil and screened for antifungal activity and other plant growth promoting traits. Endospore-formers were also isolated from rhizosphere soil associated with the roots of maize, wheat and kale grown in pots containing soil from the same grassland site. Microbial diversity amongst isolates showing antifungal activity was investigated using different molecular fingerprinting methods, namely, intergenic transcribed spacer–PCR (ITS-PCR), random amplified polymorphic DNA-PCR (RAPD-PCR) and 16S rRNA gene amplification and sequencing. Characterization of the active antimicrobial compound(s) associated with selected isolates was also attempted. Prior to isolating from bulk and rhizosphere soils, samples were pre-heated to eliminate heat sensitive vegetative cells. Mean endospore counts were; wheat rhizosphere, Log 6.03 c.f.u g-1 soil; maize rhizosphere, Log 5.88 c.f.u g-1 soil; kale rhizosphere Log 5.90 c.f.u g-1 soil; and bulk soil Log 5.67 c.f.u g-1soil. A total of three hundred and eighty-four isolates were screened for antagonism towards Rhizoctonia solani using dual-culture plate bioassays. Thirty four of the isolates (~9%) mostly isolated from the bulk soil inhibited R. solani at varying degrees. Differences in antimicrobial interactions were apparent in in vitro bioassay; supposedly due to different concentrations and/or types of antimicrobial compounds. Biochemical tests for amylase, cellulase, chitinase, and proteinase activity, siderophore production and inorganic phosphate solubilisation were conducted. None of the isolates possessed all of these attributes and only a few showed multiple traits. Ninety-one percent of the isolates exhibited proteinase activity, 76% were able to hydrolyze starch whereas only four displayed cellulase activity. Only four isolates from the bulk-soil were capable of solubilising inorganic phosphate. ITS-PCR and 16S rRNA gene sequence analysis showed high levels of genetic homology amongst isolates and the majority were closely associated with representatives of the B. cereus group. Isolate C76 was the exception, being closely matched with B. subtilis. ITS-PCR banding profile was useful for distinguishing between species but did not distinguish within species. RAPD-PCR distinguished finer levels of genetic diversity between and within sample sets, with primer OPG-11 showing the greatest levels of heterogeneity. DNA extraction methods and the influence of template DNA dilution were investigated to determine their influence on RAPD-PCR analysis reproducibility. Prominent bands were comparable for crude template- and kit-extracted DNA but slight changes in… Advisors/Committee Members: Hunter, Charles Haig. (advisor).

Subjects/Keywords: Microbiology.

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Musoke, J. (2011). Investigation into the diversity of antifungal aerobic endospore-forming bacteria associated with bulk and crop rhizosphere soil. (Masters Thesis). University of KwaZulu-Natal. Retrieved from http://hdl.handle.net/10413/8057

Chicago Manual of Style (16^th Edition):

Musoke, Jolly. “Investigation into the diversity of antifungal aerobic endospore-forming bacteria associated with bulk and crop rhizosphere soil.” 2011. Masters Thesis, University of KwaZulu-Natal. Accessed April 16, 2021. http://hdl.handle.net/10413/8057.

MLA Handbook (7^th Edition):

Musoke, Jolly. “Investigation into the diversity of antifungal aerobic endospore-forming bacteria associated with bulk and crop rhizosphere soil.” 2011. Web. 16 Apr 2021.

Vancouver:

Musoke J. Investigation into the diversity of antifungal aerobic endospore-forming bacteria associated with bulk and crop rhizosphere soil. [Internet] [Masters thesis]. University of KwaZulu-Natal; 2011. [cited 2021 Apr 16]. Available from: http://hdl.handle.net/10413/8057.

Council of Science Editors:

Musoke J. Investigation into the diversity of antifungal aerobic endospore-forming bacteria associated with bulk and crop rhizosphere soil. [Masters Thesis]. University of KwaZulu-Natal; 2011. Available from: http://hdl.handle.net/10413/8057

University of KwaZulu-Natal

26. Hunter, Charles Haig. Screening of aerobic endospore-forming bacterial isolates as candidate biocontrol agents against rhizoctonia solani.

Degree: 2016, University of KwaZulu-Natal

URL: http://hdl.handle.net/10413/13965

► Bacterial-based biocontrol of soil-borne phytopathogens has gained prominence as a promising technology for developing sustainable agricultural pest control practices. Aerobic endospore-forming bacteria are seen as… (more)

▼ Bacterial-based biocontrol of soil-borne phytopathogens has gained prominence as a promising technology for developing sustainable agricultural pest control practices. Aerobic endospore-forming bacteria are seen as potential candidates for biocontrol applications due to various ecological and physiological traits which have been shown to influence plant health and disease control. Their ability to produce endospores also provides a major commercial advantage over non spore-forming bacteria. Appropriate screening methods are central to the discovery of successful biocontrol agents and should ideally be both ecologically relevant and able to evaluate a large number of isolates. A study was therefore undertaken with the aim of establishing screening methods that facilitate the selection of aerobic endospore-forming bacteria as candidate biocontrol agents against Rhizoctonia solani, an economically important fungal pathogen exhibiting a wide host range. Aerobic endospore-forming bacteria were isolated from rhizosphere material of five crop types grown in composted pine bark medium and screened for R. solani antagonism using traditional in vitro dual-culture bioassays. Isolates exhibiting antifungal activity were then evaluated in vivo for biocontrol activity against R. solani in cucumber seedling trials. Selected isolates were evaluated further using several screening approaches including: genomic fingerprinting; characterization of, and PCR-based screening for genes involved in the biosynthesis of bioactive lipopeptide compounds; and, the use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) as a means of rapidly screening bacterial isolates. Approximately 6% of the bacterial isolates (n=400) showed antagonism towards R. solani in vitro. Dual-culture bioassays against R. solani, Fusarium oxysporum, Botrytis cinerea and Pythium arrhenomanes revealed that the antagonistic activity amongst isolates varied considerably and was influenced by the duration of the assay. From these assays it was possible to rank isolates based on the extent and stability of the inhibitory response in vitro as well as by the spectrum of antifungal activity observed. Twenty-four isolates were selected for in vivo screening for biocontrol activity against R. solani, using susceptible cucumber plants grown under greenhouse conditions. In preliminary experiments the pathogen loading rates were shown to have a marked influence on disease severity. In experiments where R. solani was seeded in the form of colonized agar plugs, significant differences between treatments and controls were recorded and several potential biocontrol candidates were identified. A general observation was that isolates that achieved high rankings in vitro performed better in the in vivo trial than those with lesser rankings; although some exceptions were noted. These findings support the notion that fungal antagonism is an important determinant of biocontrol potential that can be used in… Advisors/Committee Members: Schmidt, Stefan. (advisor), Laing, Mark Delmege. (advisor), Wallis, Frederick Michael. (advisor).

Subjects/Keywords: Microbiology.

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APA (6^th Edition):

Hunter, C. H. (2016). Screening of aerobic endospore-forming bacterial isolates as candidate biocontrol agents against rhizoctonia solani. (Thesis). University of KwaZulu-Natal. Retrieved from http://hdl.handle.net/10413/13965

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Hunter, Charles Haig. “Screening of aerobic endospore-forming bacterial isolates as candidate biocontrol agents against rhizoctonia solani.” 2016. Thesis, University of KwaZulu-Natal. Accessed April 16, 2021. http://hdl.handle.net/10413/13965.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Hunter, Charles Haig. “Screening of aerobic endospore-forming bacterial isolates as candidate biocontrol agents against rhizoctonia solani.” 2016. Web. 16 Apr 2021.

Vancouver:

Hunter CH. Screening of aerobic endospore-forming bacterial isolates as candidate biocontrol agents against rhizoctonia solani. [Internet] [Thesis]. University of KwaZulu-Natal; 2016. [cited 2021 Apr 16]. Available from: http://hdl.handle.net/10413/13965.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Hunter CH. Screening of aerobic endospore-forming bacterial isolates as candidate biocontrol agents against rhizoctonia solani. [Thesis]. University of KwaZulu-Natal; 2016. Available from: http://hdl.handle.net/10413/13965

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of KwaZulu-Natal

27. Vaughan, Halina. Design, optimisation and costing of a novel forced-upflow bioreactor for bioremediation of leachates from selected landfill sites in KwaZulu-Natal.

Degree: PhD, Microbiology, 2011, University of KwaZulu-Natal

URL: http://hdl.handle.net/10413/8604

► Most waste generated in South Africa is sent to landfills for disposal, and although it is confined in specific areas, it can potentially affect both… (more)

▼ Most waste generated in South Africa is sent to landfills for disposal, and although it is confined in specific areas, it can potentially affect both above and below ground water resources, impacting environmental and public health. This is particularly relevant in a country where water supplies are limited and groundwater resources are prone to pollution. The primary objective of this study was to assess the performance of an upflow packed-bed bioreactor purposedesigned for the treatment of leachates produced by landfills in the Durban Metropolitan Area (DMA). The effect of parameters such as the nature of the biofilm support matrix, aeration rate and recycle rate on the efficacy of the system were investigated. Another major aim of the project was to develop a low maintenance technology that could, nonetheless, bioremediate leachate effectively at minimum cost. This aspect of process design is a crucial factor in areas where there is a shortage of both funds and skilled labour. The glass 132 l packed-bed upflow bioreactor was evaluated by measuring its efficiency in terms of chemical oxygen demand (COD) and biological oxygen demand (BOD) reduction and ammonia removal. The bioreactor could be configured as a batch-type system, which was useful for comparing operating conditions; or as a continuous cascade system, which was used to assess its overall performance. Different biofilm support matrices viz. various grades of pine bark, plastic bioballs and ceramic noodles were evaluated in 22 l batch-type reactors. Leachates from five landfill sites were remediated during the course of the study, and only the leachate from Shongweni landfill, which had a remarkably low BOD:COD ratio (0.05), was intractable and could not be successfully treated; even in flask trials designed to test strategies such as augmentation of microflora and biostimulation. The other leachates investigated were from the Umlazi, Marianhill, Bisarsar Road (all general sites) and Bul-Bul Drive (a semi-hazardous site) landfills, all of which were remediated to some degree. Originally, leachate from the Umlazi landfill site was used, but it became unavailable when the site closed enforcing the use of other leachates for the remainder of the investigation. Leachates from Marianhill, Bisarsar Road and Bul-Bul Drive were treated simultaneously in duplicate operating the six-chambered bioreactor in the batchtype configuration. The highest COD removal efficiency (49 %) was obtained in the chambers treating the Bul-Bul Drive leachate, which was therefore used for further investigations. This leachate had the highest BOD:COD ratio and was therefore expected to be the most suited to biological remediation. The bioreactor performed best when plastic bioballs were used as biofilm support matrix with a relatively low level of aeration, although the uncomposted form of pine bark was used initially as the support matrix because it is inexpensive and readily available in South Africa. However, although satisfactory COD reduction… Advisors/Committee Members: Tivchev, George V. (advisor), Wallis, Frederick Michael. (advisor), Laing, Mark Delmege. (advisor).

Subjects/Keywords: Microbiology.

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Vaughan, H. (2011). Design, optimisation and costing of a novel forced-upflow bioreactor for bioremediation of leachates from selected landfill sites in KwaZulu-Natal. (Doctoral Dissertation). University of KwaZulu-Natal. Retrieved from http://hdl.handle.net/10413/8604

Chicago Manual of Style (16^th Edition):

Vaughan, Halina. “Design, optimisation and costing of a novel forced-upflow bioreactor for bioremediation of leachates from selected landfill sites in KwaZulu-Natal.” 2011. Doctoral Dissertation, University of KwaZulu-Natal. Accessed April 16, 2021. http://hdl.handle.net/10413/8604.

MLA Handbook (7^th Edition):

Vaughan, Halina. “Design, optimisation and costing of a novel forced-upflow bioreactor for bioremediation of leachates from selected landfill sites in KwaZulu-Natal.” 2011. Web. 16 Apr 2021.

Vancouver:

Vaughan H. Design, optimisation and costing of a novel forced-upflow bioreactor for bioremediation of leachates from selected landfill sites in KwaZulu-Natal. [Internet] [Doctoral dissertation]. University of KwaZulu-Natal; 2011. [cited 2021 Apr 16]. Available from: http://hdl.handle.net/10413/8604.

Council of Science Editors:

Vaughan H. Design, optimisation and costing of a novel forced-upflow bioreactor for bioremediation of leachates from selected landfill sites in KwaZulu-Natal. [Doctoral Dissertation]. University of KwaZulu-Natal; 2011. Available from: http://hdl.handle.net/10413/8604

University of KwaZulu-Natal

28. Rajpal, Desireé Alvika. Soil microbial responses to simulated climate change drivers.

Degree: 2014, University of KwaZulu-Natal

URL: http://hdl.handle.net/10413/12472

► Climate change is one of the biggest environmental challenges being experienced in the 21st century and is expected to continue to cause drastic alterations to… (more)

▼ Climate change is one of the biggest environmental challenges being experienced in the 21st century and is expected to continue to cause drastic alterations to the hydrological, biological and ecological ecosystems. Soil, the second largest carbon pool after the oceans, is a major factor in the global response towards climate change. The ability of soil to act as a sink or source of carbon as climate change increases can be influenced by soil microbial activity. Soil microbial activity is a key driver of terrestrial ecosystem functions and is extremely sensitive towards climate changes. Therefore, the main objective of this study was to investigate the effects of individual and/or interactive global change factors on soil microbial activity and diversity under elevated or ambient temperature incubations during the spring and summer seasons. This was accomplished by the addition of carbon dioxide (CO2), methane (CH4) or simulated rainfall to soil over a 60-day period using Screen Aided Carbon Dioxide Control experiments. Soil microbial dehydrogenase, urease, arylsulphatase and β-glucosidase activities were determined using standard enzyme assays over the 60-day period. In spring, the soil dehydrogenase and arylsulphatase activities increased by 28.07% and 28.48%, respectively, after the addition of elevated CO2 under elevated temperature. Lower dehydrogenase activities were observed at day 60 for most plots during summer while β-glucosidase activity was unaffected by the addition of single or multiple global change drivers during spring. In summer however, all treatments resulted in 28.05 - 36.39% higher β-glucosidase activity by day 15, compared to day 0. Urease enzyme activity was higher during spring at both temperature conditions indicating that moisture limitation and temperature change constrained the urease enzyme production during the summer period. Neither the combination of elevated CO2 and rainfall nor the combination of elevated CO2, rainfall and methane induced substantial changes to the enzyme activities during both seasons, suggesting an antagonistic effect of the combination of these global change factors. However, differences observed from a combination of elevated CO2 at higher temperature clearly reflect a potential for interaction that will affect soil enzymes and subsequent nutrient cycling. This study also investigated the changes in the soil bacterial RuBisCo gene (cbbL), important for CO2 fixation and the corresponding changes in soil organic carbon (SOC), upon exposure to various single or multiple global change drivers. Lowest cbbL gene copy numbers were observed during summer, while, during spring, the cbbL gene copy numbers increased (90.9 – 93.09%) by day 60 compared to day 0, under elevated temperatures. The combination of global change drivers did not result in a substantial variation in cbbL gene copy numbers across seasons suggesting a counteractive effect of the factors, similar to changes in soil microbial enzyme activity. No direct correlation between changes in copy number and… Advisors/Committee Members: Pillay, Balakrishna. (advisor).

Subjects/Keywords: Microbiology.

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Rajpal, D. A. (2014). Soil microbial responses to simulated climate change drivers. (Thesis). University of KwaZulu-Natal. Retrieved from http://hdl.handle.net/10413/12472

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Rajpal, Desireé Alvika. “Soil microbial responses to simulated climate change drivers.” 2014. Thesis, University of KwaZulu-Natal. Accessed April 16, 2021. http://hdl.handle.net/10413/12472.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Rajpal, Desireé Alvika. “Soil microbial responses to simulated climate change drivers.” 2014. Web. 16 Apr 2021.

Vancouver:

Rajpal DA. Soil microbial responses to simulated climate change drivers. [Internet] [Thesis]. University of KwaZulu-Natal; 2014. [cited 2021 Apr 16]. Available from: http://hdl.handle.net/10413/12472.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Rajpal DA. Soil microbial responses to simulated climate change drivers. [Thesis]. University of KwaZulu-Natal; 2014. Available from: http://hdl.handle.net/10413/12472

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of KwaZulu-Natal

29. Naidoo, Aileen. Impact of irrigation water on the quality of fresh produce.

Degree: Microbiology, 2011, University of KwaZulu-Natal

URL: http://hdl.handle.net/10413/14037

► The consumption of minimally processed fresh fruit and vegetables has increased over the past years, mostly because of consumers awareness that fresh produce serves as… (more)

▼ The consumption of minimally processed fresh fruit and vegetables has increased over the past years, mostly because of consumers awareness that fresh produce serves as a good source of vitamins, minerals and fibre. Although fresh produce is important for the human diet it may provide an optimal environment for the growth and proliferation of pathogenic microorganisms, from cultivation to processing. Several outbreaks of disease, associated with the consumption of fresh produce, have been reported worldwide. In addition, fresh produce can become contaminated by heavy metals imposing a public health concern. One of the major sources of contamination is irrigation water, as it may contain pathogens and heavy metals from upstream operations. Irrigation water has been previously shown to be associated with the contamination of fresh produce. Therefore the objective of this study was to evaluate the microbial- and heavy metal- content of irrigation water used by local farmers in KwaZulu-Natal (KZN) over a 12- month period, in order to establish a link between the water quality and the safety of fresh produce, and to develop a suitable method to reduce the microbial contamination of fresh produce during both pre- and post-harvest phases. The microbial quality of the water and fresh produce samples was determined using the membrane filtration and standard spread-plate techniques, respectively. The heavy metal content of the water and fresh produce samples were analysed using inductively coupled plasma optical emission spectrophotometry (ICP-OES). Presumptive Escherichia coli, Salmonella spp., Shigella spp. and coliform counts in the water samples were high during the sampling period. Presumptive E. coli exceeded the DWAF limit of 2×10³ cfu/100 ml for E. coli in irrigation water, in some instances. High counts of presumptive coliforms, Shigella spp. and Campylobacter spp. were recorded in the fresh produce, throughout the sampling period. The roots of the plant demonstrated the highest microbial and heavy metal contamination. Leafy vegetables such as spinach and lettuce were more contaminated than the other fresh produce sampled; for example, Campylobacter spp. exceeded 4.5×10⁵ cfu/g in crisphead lettuce. With regard to the heavy metal content of the irrigation water and the fresh produce, mercury (Hg) exceeded the FAO and WHO limit of 0.001 mg/L, throughout the sampling period, with the highest concentration of 0.057 mg/L obtained from irrigation water. Since the concentrations of Hg in both the irrigation water and fresh produce were the highest during the same period, such as in winter, a clear link can be seen between the irrigation water and fresh produce. The method used during the pre-harvest phase, in order to reduce pathogens from produce, was the effect of Pseudomonas aeruginosa on the uptake of pathogens to the fresh produce. Inhibition assays were employed to determine whether P. aeruginosa could inhibit the pathogens (E. coli, Listeria monocytogenes, Salmonella spp. and Shigella… Advisors/Committee Members: Pillay, Balakrishna. (advisor), Olaniran, Ademola Olufolahan. (advisor).

Subjects/Keywords: Microbiology.

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Naidoo, A. (2011). Impact of irrigation water on the quality of fresh produce. (Thesis). University of KwaZulu-Natal. Retrieved from http://hdl.handle.net/10413/14037

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Naidoo, Aileen. “Impact of irrigation water on the quality of fresh produce.” 2011. Thesis, University of KwaZulu-Natal. Accessed April 16, 2021. http://hdl.handle.net/10413/14037.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Naidoo, Aileen. “Impact of irrigation water on the quality of fresh produce.” 2011. Web. 16 Apr 2021.

Vancouver:

Naidoo A. Impact of irrigation water on the quality of fresh produce. [Internet] [Thesis]. University of KwaZulu-Natal; 2011. [cited 2021 Apr 16]. Available from: http://hdl.handle.net/10413/14037.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Naidoo A. Impact of irrigation water on the quality of fresh produce. [Thesis]. University of KwaZulu-Natal; 2011. Available from: http://hdl.handle.net/10413/14037

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Duke University

30. Bloom, Rachael Jin. High-throughput isolation and culture of human gut bacteria with droplet microfluidics .

Degree: 2019, Duke University

URL: http://hdl.handle.net/10161/19871

► Isolation and culture of gut bacteria enable testing for microbial roles in disease and may also lead to novel therapeutics. However, characterization of these… (more)

Subjects/Keywords: Microbiology

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Bloom, R. J. (2019). High-throughput isolation and culture of human gut bacteria with droplet microfluidics . (Thesis). Duke University. Retrieved from http://hdl.handle.net/10161/19871

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Bloom, Rachael Jin. “High-throughput isolation and culture of human gut bacteria with droplet microfluidics .” 2019. Thesis, Duke University. Accessed April 16, 2021. http://hdl.handle.net/10161/19871.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Bloom, Rachael Jin. “High-throughput isolation and culture of human gut bacteria with droplet microfluidics .” 2019. Web. 16 Apr 2021.

Vancouver:

Bloom RJ. High-throughput isolation and culture of human gut bacteria with droplet microfluidics . [Internet] [Thesis]. Duke University; 2019. [cited 2021 Apr 16]. Available from: http://hdl.handle.net/10161/19871.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Bloom RJ. High-throughput isolation and culture of human gut bacteria with droplet microfluidics . [Thesis]. Duke University; 2019. Available from: http://hdl.handle.net/10161/19871

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

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Open Access Theses and Dissertations