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You searched for +publisher:"Texas A&M University" +contributor:("Skare, Jonathon"). Showing records 1 – 3 of 3 total matches.

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1. Reynolds, Mollie Megan. Identification of Novel Virulence Genes of Salmonella enterica Using an Array Based Analysis of Cistrons Under Selection.

Degree: PhD, Genetics, 2011, Texas A&M University

Pools of mutants of minimal complexity but maximal coverage of genes of interest facilitate screening for genes under selection in a particular environment. Prior to this work, mutants were generated by random transposon insertions, which yielded highly complex pools for in vivo studies. Recent advances in polymerase chain reaction (PCR)-based mutagenesis in bacteria using the lambda red recombinase, as well as whole genome sequencing, enable a more directed approach for the generation of mutants. The lambda red approach was used to construct individual mutants in 1,023 Salmonella enterica serovar Typhimurium genes, including almost all genes found in Salmonella, but not in related genera. All the mutations were confirmed simultaneously using a novel amplification strategy to produce labeled ribonucleic acid (RNA) from a T7 RNA polymerase promoter, introduced during the construction of each mutant, followed by hybridization of this labeled RNA to a Typhimurium genome tiling array. To demonstrate the ability to identify fitness phenotypes using our pool of mutants, the pool was subjected to selection by intraperitoneal injection into BALB/c (Bagg Albino) mice and was recovered from the spleen. Changes in the representation of each mutant were monitored using T7 transcripts hybridized to a novel inexpensive minimal microarray. Among the top 120 statistically significant spleen colonization phenotypes, 51 were mutations in genes with no previously known role in this model. Fifteen phenotypes were tested using individual mutants in competitive assays and eleven were confirmed in individual mixed intraperitoneal infection in mice, including the first two examples of attenuation for sRNA mutants in Salmonella. We refer to our method as Array-Based Analysis of Cistrons Under Selection (ABACUS). Among the confirmed mutants identified in the ABACUS screen was a component of the twin arginine transport (Tat) system, tatC, required for transport of folded proteins across the cellular membrane. TatC is the highly conserved component necessary for recognition of the twin arginine containing signal sequence S/T-R-R-x-FL- K. We confirmed [delta] tatC mutants are defective for colonization of the liver and spleen in competitive infections with wild type ATCC14028 after intraperitoneal infection in Salmonella- susceptible (BALB/c). We also found that [delta] tatC mutants were defective for swimming motility, but not swarming motility, which was linked to the ability to elaborate flagellins on the bacterial surface under different conditions. Advisors/Committee Members: Andrews-Polymenis, Helene L. (committee member), Adams, Garry (committee member), Samuel, James (committee member), Skare, Jonathon (committee member).

Subjects/Keywords: ABACUS; Salmonella; genetic screens; Twin arginine transport; motility

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APA (6th Edition):

Reynolds, M. M. (2011). Identification of Novel Virulence Genes of Salmonella enterica Using an Array Based Analysis of Cistrons Under Selection. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7675

Chicago Manual of Style (16th Edition):

Reynolds, Mollie Megan. “Identification of Novel Virulence Genes of Salmonella enterica Using an Array Based Analysis of Cistrons Under Selection.” 2011. Doctoral Dissertation, Texas A&M University. Accessed March 09, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7675.

MLA Handbook (7th Edition):

Reynolds, Mollie Megan. “Identification of Novel Virulence Genes of Salmonella enterica Using an Array Based Analysis of Cistrons Under Selection.” 2011. Web. 09 Mar 2021.

Vancouver:

Reynolds MM. Identification of Novel Virulence Genes of Salmonella enterica Using an Array Based Analysis of Cistrons Under Selection. [Internet] [Doctoral dissertation]. Texas A&M University; 2011. [cited 2021 Mar 09]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7675.

Council of Science Editors:

Reynolds MM. Identification of Novel Virulence Genes of Salmonella enterica Using an Array Based Analysis of Cistrons Under Selection. [Doctoral Dissertation]. Texas A&M University; 2011. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7675


Texas A&M University

2. Skwor, Troy Arthur. The role of CCL5 (RANTES) in the immune response against Mycobacterium tuberculosis in the guinea pig.

Degree: PhD, Medical Sciences, 2005, Texas A&M University

Tuberculosis is the second leading cause of morbidity and mortality worldwide due to an infectious disease. Development of a new tuberculosis (TB) vaccine would be facilitated by a better understanding of the mechanisms of protection induced by the current TB vaccine, Mycobacterium bovis BCG. Recombinant guinea pig (rgp)CCL5 and anti-rgpCCL5 were developed and characterized. The biological activity of rgpCCL5 was determined in a chemotaxis assay using T lymphocytes and pleural exudate cells. The specificity of rabbit anti-rgpCCL5 polyclonal antibody was confirmed by Western blot. RgpCCL5 was used to stimulate alveolar and peritoneal macrophages in vitro. and cytokine/chemokine gene expression was evaluated using real-time PCR. RgpCCL5 stimulated TNFα, IL-1β, CCL2, and CXCL8 mRNA expression and TNFα protein production (as assessed in the L929 cell bioassay) in macrophages. The effect of BCG-vaccination on CCL5 expression and production in leukocytes infected with M. tuberculosis was examined in vitro and in vivo. Polyclonal anti-rgpCCL5 was used to develop an ELISA assay to quantify gpCCL5 protein levels, and real-time PCR was used to detect CCL5 mRNA. Leukocytes isolated from BCG-vaccinated guinea pigs and infected in vitro with virulent M. tuberculosis demonstrated significantly elevated gpCCL5 mRNA and protein compared to cells from naive animals. The response of gpCCL5 to M. tuberculosis in vivo was studied in tuberculous pleural effusions, where peak levels of CCL5 mRNA and protein were reached at day 4 post-induction. Disease severity, cellular differentiation, histology, and cytokine/chemokine mRNA levels in pleural cells and granulomas were analyzed on day 4 in guinea pigs induced with tuberculous pleurisy and treated with either rgpCCL5 or anti-rgpCCL5 by direct intra-pleural injection. In these studies, neutralizing CCL5 resulted in reduced macrophage accumulation, diminished levels of IFNγ, TNFα, and CCL5 mRNA in pleural effusion cells, and reduced spontaneous lymphocyte proliferation. Together these studies suggest an important role for gpCCL5 in activating leukocytes during M. tuberculosis infection. Advisors/Committee Members: McMurray, David (advisor), Welsh, Jane (committee member), Skare, Jonathon (committee member), Tesh, Vernon (committee member).

Subjects/Keywords: RANTES; chemokines; Mycobacterium tuberculosis; cytokines; pleurisy; macrophages

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

APA (6th Edition):

Skwor, T. A. (2005). The role of CCL5 (RANTES) in the immune response against Mycobacterium tuberculosis in the guinea pig. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/1506

Chicago Manual of Style (16th Edition):

Skwor, Troy Arthur. “The role of CCL5 (RANTES) in the immune response against Mycobacterium tuberculosis in the guinea pig.” 2005. Doctoral Dissertation, Texas A&M University. Accessed March 09, 2021. http://hdl.handle.net/1969.1/1506.

MLA Handbook (7th Edition):

Skwor, Troy Arthur. “The role of CCL5 (RANTES) in the immune response against Mycobacterium tuberculosis in the guinea pig.” 2005. Web. 09 Mar 2021.

Vancouver:

Skwor TA. The role of CCL5 (RANTES) in the immune response against Mycobacterium tuberculosis in the guinea pig. [Internet] [Doctoral dissertation]. Texas A&M University; 2005. [cited 2021 Mar 09]. Available from: http://hdl.handle.net/1969.1/1506.

Council of Science Editors:

Skwor TA. The role of CCL5 (RANTES) in the immune response against Mycobacterium tuberculosis in the guinea pig. [Doctoral Dissertation]. Texas A&M University; 2005. Available from: http://hdl.handle.net/1969.1/1506


Texas A&M University

3. Endicott-Yazdani, Tiana. Identification of Novel Salmonella Typhimurium Genes Required For Survival During Intestinal Inflammation.

Degree: PhD, Microbial & Molecular Pathogenesis, Texas A&M University

Bovine ligated ileal loops provide the best model to examine Salmonella Typhimurium genes required for survival during the early stages of infection, as humans and cattle develop very similar intestinal pathogenesis in response to the organism. Utilizing pools of mutants, both single gene and multi-gene deletion mutants, much of the S. Typhimurium genome can be screened simultaneously. A library consisting of multi-gene deletion mutants was screened in ligated ileal loops in calves. Regions of the genome required for survival in this model were identified in mucus and tissue samples using microarray analysis. STM1187-90 was one such region identified as under selection in both mucus and tissue. A ASTM1188 mutant was confirmed to poorly colonize the intestinal mucus and tissue in the presence of inflammation in competitive infections with the wild type. Complementation in trans reversed the phenotype of the ASTM1188 mutant. The phenotype of the ASTM1188 mutant was replicated and complemented in trans in the murine colitis model. STM1188 is a Salmonella specific gene whose protein product we show to be located in the inner membrane. This gene is absent in host-adapted serovars S. Typhi and S. Paratyphi A. Mutation of the putative lipobox cysteine to alanine resulted in mis- localization of STM1188C24A to the cytoplasm, and the inability to complement ASTM1188 in trans in mice. A second screen of a single gene deletion pool (SGD) identified many novel genes with potential roles during inflammation as well as many predicted genes with defined roles during the early stages of infection. Several novel gene phenotypes were confirmed and subsequently complemented in competitive infections with wild type. AhilE was identified during SGD screening and confirmed in bovine ligated ileal loops as being selected against during competitive infections with extensive inflammation, however, it was not selected against when the inflammatory immune response was limited. HilE has been previously shown to negatively regulate SPI-1 expression. Utilizing the murine colitis model, the AhilE phenotype was confirmed and complemented during competitive infection with wild type. By using (3-galactosidase assays, AhilE was confirmed to overexpress SPI-1, however, surprisingly AhilE also overexpressed SPI-2 during SPI-1 inducing conditions. In the current studies we performed Salmonella screens in bovine ligated ileal loops and confirmed novel virulence genes required for survival during inflammation. Advisors/Committee Members: Adams, L. Garry (committee member), Skare, Jonathon (committee member), Tesh, Vernon (committee member), Andrews-Polymenis, Helene (committeechair).

Subjects/Keywords: Biomedical Sciences

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APA (6th Edition):

Endicott-Yazdani, T. (n.d.). Identification of Novel Salmonella Typhimurium Genes Required For Survival During Intestinal Inflammation. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/154260

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Chicago Manual of Style (16th Edition):

Endicott-Yazdani, Tiana. “Identification of Novel Salmonella Typhimurium Genes Required For Survival During Intestinal Inflammation.” Doctoral Dissertation, Texas A&M University. Accessed March 09, 2021. http://hdl.handle.net/1969.1/154260.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

MLA Handbook (7th Edition):

Endicott-Yazdani, Tiana. “Identification of Novel Salmonella Typhimurium Genes Required For Survival During Intestinal Inflammation.” Web. 09 Mar 2021.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Vancouver:

Endicott-Yazdani T. Identification of Novel Salmonella Typhimurium Genes Required For Survival During Intestinal Inflammation. [Internet] [Doctoral dissertation]. Texas A&M University; [cited 2021 Mar 09]. Available from: http://hdl.handle.net/1969.1/154260.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Council of Science Editors:

Endicott-Yazdani T. Identification of Novel Salmonella Typhimurium Genes Required For Survival During Intestinal Inflammation. [Doctoral Dissertation]. Texas A&M University; Available from: http://hdl.handle.net/1969.1/154260

Note: this citation may be lacking information needed for this citation format:
No year of publication.

.