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Georgia Tech
1.
Perez Cuevas, Monica Beatriz.
Hepatitis B vaccination using a dissolvable microneedle patch.
Degree: MS, Chemical and Biomolecular Engineering, 2017, Georgia Tech
URL: http://hdl.handle.net/1853/59807 
► Despite improved vaccination rates against hepatitis B, there remain critical barriers to addressing gaps in vaccination coverage. The need of an effective supply chain, vaccine…
(more)
▼ Despite improved vaccination rates against hepatitis B, there remain critical barriers to addressing gaps in vaccination coverage. The need of an effective supply chain, vaccine waste management, trained healthcare providers and cost are all issues that impede mass vaccination campaigns around the world. Microneedle patches have been proposed as an alternative mode of vaccination. Microneedle patches consist of micron-scale projections that are capable of disrupting the stratum corneum by creating holes in the skin to deliver therapeutic agents. Small and lightweight, microneedle patches are a promising alternative to the bulky multi-dose vials and syringes currently used in mass vaccination campaigns. Furthermore, the high density of antigen presenting cells in the the skin make transcutaneous immunization via microneedles advantageous, as they target vaccine cargo to the topmost layer of the skin. The key goal of this project was to develop a microneedle patch for hepatitis B vaccination that is simple to administer and of comparable immunogenicity to conventional intramuscular vaccination. Trehalose was used as a stabilizing excipient for both coated metal and dissolvable microneedles. Moreover, patches were used in vivo to compare the elicited immune response in both mice and rhesus macaques. Additionally, the mechanical properties of our microneedle patch were evaluated via both theoretical and experimental approaches to predict failure force. This work shows that microneedle patches can successfully encapsulate and deliver hepatitis B antigen to generate a strong and sustained immune response in multiple animal models.
Advisors/Committee Members: Prausnitz, Mark R. (advisor), Garcia, Andres J. (committee member), Bommarius, Andreas S. (committee member).
Subjects/Keywords: Microneedles; Hepatitis b
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APA (6th Edition):
Perez Cuevas, M. B. (2017). Hepatitis B vaccination using a dissolvable microneedle patch. (Masters Thesis). Georgia Tech. Retrieved from http://hdl.handle.net/1853/59807
Chicago Manual of Style (16th Edition):
Perez Cuevas, Monica Beatriz. “Hepatitis B vaccination using a dissolvable microneedle patch.” 2017. Masters Thesis, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/59807.
MLA Handbook (7th Edition):
Perez Cuevas, Monica Beatriz. “Hepatitis B vaccination using a dissolvable microneedle patch.” 2017. Web. 06 Mar 2021.
Vancouver:
Perez Cuevas MB. Hepatitis B vaccination using a dissolvable microneedle patch. [Internet] [Masters thesis]. Georgia Tech; 2017. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/59807.
Council of Science Editors:
Perez Cuevas MB. Hepatitis B vaccination using a dissolvable microneedle patch. [Masters Thesis]. Georgia Tech; 2017. Available from: http://hdl.handle.net/1853/59807
Georgia Tech
2.
Kwok, Thomas Tai-min.
Process engineering for lignin value prior to pulping.
Degree: PhD, Chemical and Biomolecular Engineering, 2019, Georgia Tech
URL: http://hdl.handle.net/1853/62663
► Biomass pretreatment unlocks chemical moieties for downstream valorization. This thesis focuses on organic solvent pretreatments that complement pulp production by delivering an additional lignin stream…
(more)
▼ Biomass pretreatment unlocks chemical moieties for downstream valorization. This thesis focuses on organic solvent pretreatments that complement pulp production by delivering an additional lignin stream for the production of renewable chemicals. This work proposes and assesses a next-generation pulping process named Lignin Value Prior to Pulping (LVPP). Tools are developed to measure treatment efficacy, rank solvents for LVPP, and describe the process of retrofitting a pulp mill. This thesis presents Direct Yellow 11 as a replacement for Direct Orange 15 to measure cellulose accessibility, compare organic solvents, and enhance a cellulose conversion rate model. Additional screens and metrics are established to compare organic solvents within a solvent selection guide for LVPP. A set of solvents are evaluated using performance, hazard, exposure, cost, and process economic metrics. From this selection guide, 1,6 hexamethylenediamine, diethanolamine, propylene glycol, and 1-methyl piperazine are recommended for additional process development. A complete process design is presented for an LVPP treatment with 1,6 hexamethylenediamine, and a techno-economic analysis yields a minimum lignin selling price of $0.829/kg for economic viability. By incorporating an integrated computational and experimental technique, this thesis presents process and cost models that highlight feasibility constraints and technological barriers to future LVPP processes. This thesis aids the diversification of the pulp and paper industry towards new products, and it pushes the field towards favorable economics for renewable chemicals.
Advisors/Committee Members: Bommarius, Andreas S. (advisor), Realff, Matthew J. (advisor), Luettgen, Christopher O. (committee member), Peralta-Yahya, Pamela P. (committee member), Sievers, Carsten (committee member).
Subjects/Keywords: Lignocellulosic biomass; Techno-economics; Lignin value prior to pulping; Solvent selection; Delignification; Pretreatment; Pulping; Organosolv
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APA (6th Edition):
Kwok, T. T. (2019). Process engineering for lignin value prior to pulping. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/62663
Chicago Manual of Style (16th Edition):
Kwok, Thomas Tai-min. “Process engineering for lignin value prior to pulping.” 2019. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/62663.
MLA Handbook (7th Edition):
Kwok, Thomas Tai-min. “Process engineering for lignin value prior to pulping.” 2019. Web. 06 Mar 2021.
Vancouver:
Kwok TT. Process engineering for lignin value prior to pulping. [Internet] [Doctoral dissertation]. Georgia Tech; 2019. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/62663.
Council of Science Editors:
Kwok TT. Process engineering for lignin value prior to pulping. [Doctoral Dissertation]. Georgia Tech; 2019. Available from: http://hdl.handle.net/1853/62663
Georgia Tech
3.
Bruce, Kathryn Lyn.
Roles of protein sequence and cell environment in cross-species prion transmission and amyloid interference.
Degree: PhD, Biology, 2014, Georgia Tech
URL: http://hdl.handle.net/1853/52288
► Proteinaceous infectious particles, termed 'prions' are self-perpetuating protein isoforms that transmit neurodegenerative diseases in mammals and phenotypic traits in yeast. Each conformational variant of a…
(more)
▼ Proteinaceous infectious particles, termed 'prions' are self-perpetuating protein isoforms that transmit neurodegenerative diseases in mammals and phenotypic traits in yeast. Each conformational variant of a prion protein is faithfully propagated to a homologous protein in the same cell environment. However, a reduction in the efficiency of prion transmission between different species is often observed and is termed "species barrier". Prion transmission to a heterologous protein may, in some cases, permanently change the structure of the prion variant, and divergent proteins may interfere with prion propagation in a species-specific manner. To identify the importance of both protein sequence and the cell environment on prion interference and cross-species transmission, we employed heterologous Sup35 proteins from three Saccharomyces sensu stricto species: Saccharomyces cerevisiae (Sc), Saccharomyces paradoxus (Sp), and Saccharomyces bayanus (Sb). We performed our experiments in two different cell environments (Sc and Sp). Our data show that Sup35 from one species can form a prion in another, and we employed a transfection procedure to perform cross-species transfer of the prion. Using a shuffle procedure, we demonstrate that the specificity of prion transmission is determined by the protein itself rather than the cell environment. Interestingly, we noted that variant-specific prion patterns can be altered irreversibly during cross-species transmission through
S. bayanus module II. We further show that prion interference does not always correlate with cross-species prion transmission, and the identity of particular regions or even a specific amino acid, rather than the overall level of PrD homology is crucial for determining cross-species transmission and interference. Lastly we provide evidence to suggest that prion interference is specific to the cell environment.
Advisors/Committee Members: Chernoff, Yury O. (advisor), Lobachev, Kirill S. (committee member), Storici, Francesca (committee member), Bommarius, Andreas S. (committee member), Gleason, Michael L. (committee member).
Subjects/Keywords: Prion; Amyloid; Prion interference; Saccharomyces; Species barrier; Sup35
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APA (6th Edition):
Bruce, K. L. (2014). Roles of protein sequence and cell environment in cross-species prion transmission and amyloid interference. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/52288
Chicago Manual of Style (16th Edition):
Bruce, Kathryn Lyn. “Roles of protein sequence and cell environment in cross-species prion transmission and amyloid interference.” 2014. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/52288.
MLA Handbook (7th Edition):
Bruce, Kathryn Lyn. “Roles of protein sequence and cell environment in cross-species prion transmission and amyloid interference.” 2014. Web. 06 Mar 2021.
Vancouver:
Bruce KL. Roles of protein sequence and cell environment in cross-species prion transmission and amyloid interference. [Internet] [Doctoral dissertation]. Georgia Tech; 2014. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/52288.
Council of Science Editors:
Bruce KL. Roles of protein sequence and cell environment in cross-species prion transmission and amyloid interference. [Doctoral Dissertation]. Georgia Tech; 2014. Available from: http://hdl.handle.net/1853/52288
Georgia Tech
4.
Al-Hmoud, Linda.
Understanding heterogeneous copper catalysts for coupling reactions in organic synthesis.
Degree: PhD, Chemical and Biomolecular Engineering, 2014, Georgia Tech
URL: http://hdl.handle.net/1853/52997
► Copper is an inexpensive, earth-abundant, non-toxic metal that is found to have widespread applications in catalysis. Ullmann and Ullmann-type reactions and Glaser-Hay oxidative coupling of…
(more)
▼ Copper is an inexpensive, earth-abundant, non-toxic metal that is found to have widespread applications in catalysis. Ullmann and Ullmann-type reactions and Glaser-Hay oxidative coupling of terminal alkynes are some of the well-established copper catalyzed coupling reactions used for the construction of important organic molecules, including pharmaceuticals, commodity chemicals and polymers. Those reactions have been mainly performed homogeneously, where the removal of residual copper from the reaction mixture is a challenge. Therefore, many researchers tried supporting copper precatalysts in order to help recover, and thus reduce final product contamination. Some studies showed that copper leached significantly from the support, with others showing that leached copper has a role in the catalysis. Nevertheless, many studies reported that the used supported catalysts were recyclable and claimed catalyst'
s heterogeneity. In most cases, the nature of the truly active copper species is still not clear.
The objectives of this thesis were (1) to assess the heterogeneity/homogeneity of active copper species in popular catalytic C-N coupling reactions with already studied catalysts, mainly a copper exchanged zeolite and copper oxide nanoparticles, and (2) to use the collected information in designing a truly heterogeneous (stable and recyclable) catalyst.
Initially, and because of its shape selectivity characteristics, copper-exchanged NaY zeolite, Cu(II)Y, was chosen to study the heterogeneity of copper catalyzed amination of aryl iodide with imidazole. The collected results from conducted shape selectivity tests indicated that Cu(II)Y might be heterogeneous catalyst, but because of the used base, that is crucial for this C-N coupling reaction, the crystallinity of the zeolite structure was diminished. Therefore, it was important to support copper on a framework that is stable under the basic conditions required for this type of reaction if a heterogeneous, recyclable catalyst were to be achieved. For this purpose, cerium oxide was chosen, and copper oxide supported on cerium oxide, CuO-CeO₂, was investigated as a potential heterogeneous catalyst for C-N coupling reaction. This investigation included the role of each reaction reagent in facilitating copper leaching into solution. It was found that copper leached from the support and it was demonstrated through hot filtration tests that the leached copper species was the main active catalyst. Leaching was caused by the solvent (DMSO) as well as the used reactants and the base. Similar conclusions were drawn when this CuO-CeO₂ catalyst was used for the direct synthesis of imines from amines under aerobic conditions. Although this CuO-CeO₂ catalyst has the advantages of being more recoverable and active than unsupported CuO nanoparticles at similar copper loadings, it is not fully recyclable, as the copper catalysis occurs in solution.
These findings meant that designing a truly heterogeneous catalyst for this reaction is a challenging task. Understanding the effect of each…
Advisors/Committee Members: Jones, Christopher W. (advisor), Zhang, Z. John (committee member), Soper, Jake (committee member), Agrawal, Pradeep K. (committee member), Bommarius, Andreas S. (committee member).
Subjects/Keywords: Copper catalysis; Heterogeneous catalysis; Organic synthesis
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APA (6th Edition):
Al-Hmoud, L. (2014). Understanding heterogeneous copper catalysts for coupling reactions in organic synthesis. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/52997
Chicago Manual of Style (16th Edition):
Al-Hmoud, Linda. “Understanding heterogeneous copper catalysts for coupling reactions in organic synthesis.” 2014. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/52997.
MLA Handbook (7th Edition):
Al-Hmoud, Linda. “Understanding heterogeneous copper catalysts for coupling reactions in organic synthesis.” 2014. Web. 06 Mar 2021.
Vancouver:
Al-Hmoud L. Understanding heterogeneous copper catalysts for coupling reactions in organic synthesis. [Internet] [Doctoral dissertation]. Georgia Tech; 2014. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/52997.
Council of Science Editors:
Al-Hmoud L. Understanding heterogeneous copper catalysts for coupling reactions in organic synthesis. [Doctoral Dissertation]. Georgia Tech; 2014. Available from: http://hdl.handle.net/1853/52997
Georgia Tech
5.
Mistilis, Matthew Joseph.
Thermostabilization of influenza vaccine in microneedle patches.
Degree: PhD, Chemical and Biomolecular Engineering, 2016, Georgia Tech
URL: http://hdl.handle.net/1853/58153
► Vaccine delivery to the skin via microneedles confers several advantages over the traditional hypodermic needle and syringe. This work focuses on developing microneedles as a…
(more)
▼ Vaccine delivery to the skin via microneedles confers several advantages over the traditional hypodermic needle and syringe. This work focuses on developing microneedles as a thermostable delivery method for the influenza vaccine that can be completely removed from the cold-chain, thus minimizing cost and wastage during storage and transportation. Microneedle formulations were screened for their effect on influenza vaccine activity during drying. A number of excipients, particularly the combination of arginine and heptagluconate, successfully stabilized influenza vaccine during storage in the dried state and in microneedle patches at ambient or elevated temperatures for up to eighteen months. Influenza vaccine microneedle patches were shown to be resistant against several stresses and remained immunogenic in a mouse model after long-term storage. The primary mechanism of influenza vaccine activity loss during drying was aggregation, which can be mitigated by stabilizing excipients.
Advisors/Committee Members: Prausnitz, Mark R. (advisor), Bommarius, Andreas S. (advisor), Champion, Julie A. (committee member), Compans, Richard W. (committee member), Lieberman, Raquel L. (committee member).
Subjects/Keywords: Vaccine delivery; Vaccine stability; Microneedles; Drug delivery; Formulations; Dermal delivery
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APA (6th Edition):
Mistilis, M. J. (2016). Thermostabilization of influenza vaccine in microneedle patches. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/58153
Chicago Manual of Style (16th Edition):
Mistilis, Matthew Joseph. “Thermostabilization of influenza vaccine in microneedle patches.” 2016. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/58153.
MLA Handbook (7th Edition):
Mistilis, Matthew Joseph. “Thermostabilization of influenza vaccine in microneedle patches.” 2016. Web. 06 Mar 2021.
Vancouver:
Mistilis MJ. Thermostabilization of influenza vaccine in microneedle patches. [Internet] [Doctoral dissertation]. Georgia Tech; 2016. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/58153.
Council of Science Editors:
Mistilis MJ. Thermostabilization of influenza vaccine in microneedle patches. [Doctoral Dissertation]. Georgia Tech; 2016. Available from: http://hdl.handle.net/1853/58153
Georgia Tech
6.
Au, Samantha Kaling.
Development of amine dehydrogenases toward production of chiral amines.
Degree: PhD, Chemical and Biomolecular Engineering, 2016, Georgia Tech
URL: http://hdl.handle.net/1853/58172
► One in four of the top 200 selling pharmaceutical drugs contain a chiral amine. Chiral amines often require difficult synthesis through traditional heterogeneous catalysts. As…
(more)
▼ One in four of the top 200 selling pharmaceutical drugs contain a chiral amine. Chiral amines often require difficult synthesis through traditional heterogeneous catalysts. As a result, the use of biocatalysts in industrial applications to create amines has been increasingly desired and developed. Amine dehydrogenases (AmDHs) are a novel class of enzymes that catalyze the reaction of prochiral ketones to chiral amines. Through protein engineering on existing amino acid dehydrogenase scaffolds, ketones instead of carboxylic acids are now substrates of the AmDH. This work will describe the use of biocatalysts, specifically the AmDHs, as a green alternative to catalyze ketones to enantiomerically pure amines.
Advisors/Committee Members: Bommarius, Andreas S. (advisor), Styczynski, Mark (committee member), Champion, Julie (committee member), Peralta-Yahya, Pamela (committee member), Abrahamson, Michael J. (committee member).
Subjects/Keywords: Chiral amines; Dehydrogenases; Biocatalysts
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APA (6th Edition):
Au, S. K. (2016). Development of amine dehydrogenases toward production of chiral amines. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/58172
Chicago Manual of Style (16th Edition):
Au, Samantha Kaling. “Development of amine dehydrogenases toward production of chiral amines.” 2016. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/58172.
MLA Handbook (7th Edition):
Au, Samantha Kaling. “Development of amine dehydrogenases toward production of chiral amines.” 2016. Web. 06 Mar 2021.
Vancouver:
Au SK. Development of amine dehydrogenases toward production of chiral amines. [Internet] [Doctoral dissertation]. Georgia Tech; 2016. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/58172.
Council of Science Editors:
Au SK. Development of amine dehydrogenases toward production of chiral amines. [Doctoral Dissertation]. Georgia Tech; 2016. Available from: http://hdl.handle.net/1853/58172
Georgia Tech
7.
Faraji Mosalman, Mozhdeh Sadat.
From experimental observations to a functional model of the lignin pathway: Computational modeling reveals new insights.
Degree: PhD, Mechanical Engineering, 2018, Georgia Tech
URL: http://hdl.handle.net/1853/59881
► Lignin is a natural polymer that is interwoven with cellulose and hemicellulose within plant cell walls. Due to this molecular arrangement, lignin is a major…
(more)
▼ Lignin is a natural polymer that is interwoven with cellulose and hemicellulose within plant cell walls. Due to this molecular arrangement, lignin is a major
contributor to the recalcitrance of plant materials with respect to the extraction of sugars and their fermentation into ethanol, butanol, and other potential bioenergy crops. The lignin biosynthetic pathway is similar, but not identical in different plant species. It is in each case comprised of a moderate number of enzymatic steps, but its responses to manipulations, such as gene knock-downs, are complicated by the fact that several of the key enzymes are involved in several reaction steps. This feature poses a challenge to bioenergy production, as it renders it difficult to select the most promising combinations of genetic manipulations for the optimization of lignin composition and amount. Moreover, species specific regulatory features and distinct spatial and topological characteristics hinder accuracy of a unified lignin pathway model. In this dissertation a systems biology approach is used to address these challenges by means of computational modeling. Novel mathematical techniques are employed on different types of experimental data in situ, and shed light on complexities of lignin biosynthesis pathway. The developed methods are nevertheless general enough to be used in a wide range of metabolic modeling applications.
Advisors/Committee Members: Voit, Eberhard O. (advisor), Bommarius, Andreas S. (committee member), Leamy, Michael J. (committee member), Peralta-Yahya, Pamela (committee member), Qiu, Peng (committee member).
Subjects/Keywords: Lignin; Computational modeling
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APA (6th Edition):
Faraji Mosalman, M. S. (2018). From experimental observations to a functional model of the lignin pathway: Computational modeling reveals new insights. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/59881
Chicago Manual of Style (16th Edition):
Faraji Mosalman, Mozhdeh Sadat. “From experimental observations to a functional model of the lignin pathway: Computational modeling reveals new insights.” 2018. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/59881.
MLA Handbook (7th Edition):
Faraji Mosalman, Mozhdeh Sadat. “From experimental observations to a functional model of the lignin pathway: Computational modeling reveals new insights.” 2018. Web. 06 Mar 2021.
Vancouver:
Faraji Mosalman MS. From experimental observations to a functional model of the lignin pathway: Computational modeling reveals new insights. [Internet] [Doctoral dissertation]. Georgia Tech; 2018. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/59881.
Council of Science Editors:
Faraji Mosalman MS. From experimental observations to a functional model of the lignin pathway: Computational modeling reveals new insights. [Doctoral Dissertation]. Georgia Tech; 2018. Available from: http://hdl.handle.net/1853/59881
Georgia Tech
8.
Vermeersch, Kathleen A.
Systems-level characterization of ovarian cancer metabolism.
Degree: PhD, Chemical and Biomolecular Engineering, 2014, Georgia Tech
URL: http://hdl.handle.net/1853/54258
► The purpose of this thesis was to characterize cancer metabolism in vitro using epithelial ovarian cancer as a model on an untargeted, systems-level, basis with…
(more)
▼ The purpose of this thesis was to characterize cancer metabolism in vitro using epithelial ovarian cancer as a model on an untargeted, systems-level, basis with particular attention paid to the difference between cancer stem cell metabolism and cancer cell metabolism. Two-dimensional gas chromatography coupled to mass spectrometry was used to measure the metabolite profiles of the ovarian cancer and cancer stem cell lines under normal baseline conditions and also under chemotherapeutic and environmental perturbations. These two cell lines exhibited significant metabolic differences under normal baseline conditions and results demonstrated that metabolism in the ovarian cancer stem cell line was distinct from that of more differentiated isogenic cancer cells, showing similarities to stem cell metabolism that suggest the potential importance of metabolism for the cancer stem cell phenotype. Glucose deprivation, hypoxia, and ischemia all perturbed ovarian cancer and cancer stem cell metabolism, but not in the same ways between the cell types. Chemotherapeutic treatment with docetaxel caused metabolic changes mostly in amino acid and carbohydrate metabolism in ovarian cancer cells, while ovarian cancer stem cell metabolism was not affected by docetaxel. Overall, these metabolic differences between the two cell types will deepen our understanding of the metabolic changes occurring within the in vivo tumor and will help drive development of cancer stem cell targeted therapeutics.
Advisors/Committee Members: Styczynski, Mark P. (advisor), Chen, Rachel (committee member), Bommarius, Andreas S. (committee member), Dawson, Michelle R. (committee member), McDonald, John F. (committee member).
Subjects/Keywords: Cancer stem cells; Cancer metabolism; Ovarian cancer; Metabolomics
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APA (6th Edition):
Vermeersch, K. A. (2014). Systems-level characterization of ovarian cancer metabolism. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/54258
Chicago Manual of Style (16th Edition):
Vermeersch, Kathleen A. “Systems-level characterization of ovarian cancer metabolism.” 2014. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/54258.
MLA Handbook (7th Edition):
Vermeersch, Kathleen A. “Systems-level characterization of ovarian cancer metabolism.” 2014. Web. 06 Mar 2021.
Vancouver:
Vermeersch KA. Systems-level characterization of ovarian cancer metabolism. [Internet] [Doctoral dissertation]. Georgia Tech; 2014. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/54258.
Council of Science Editors:
Vermeersch KA. Systems-level characterization of ovarian cancer metabolism. [Doctoral Dissertation]. Georgia Tech; 2014. Available from: http://hdl.handle.net/1853/54258
Georgia Tech
9.
Encarnacion-Gomez, Luis G.
Design and operation of enzymatic reactive crystallization: Applications in chiral purity and kinetically controlled synthesis.
Degree: PhD, Chemical and Biomolecular Engineering, 2015, Georgia Tech
URL: http://hdl.handle.net/1853/54322
► The work presented in this thesis is aimed to design efficient reactive crystallization operations that could potentially be implemented in the manufacture of enantiomerically pure…
(more)
▼ The work presented in this thesis is aimed to design efficient reactive crystallization operations that could potentially be implemented in the manufacture of enantiomerically pure compounds and β-lactam antibiotics. Multiple aspects of solution thermodynamics, reaction engineering and crystallization from complex solutions are involved and will be discussed in detail through the following chapters.
The first piece of this work utilizes reactive crystallization for the manufacture of enantiomerically pure amino acids. Chemo-enzymatic stereoiversion reactions are used to enrich saturated or supersaturated solutions to favor the selection of a desired enantiomer. L-Methionine and L-Phenylalanine were resolve successfully from racemic mixtures by cyclic stereoinversion. r D-amino acids were oxidized by D-amino acid oxidase (D-AAO) and the resulting ketoacid was subsequently reduced by ammonia borane producing a racemic-mixture After the necessary enantiomeric enrichment was reached, system conditions were changed to induce supersaturation and promote crystal formation. In each case crystals with chemical and enantiomeric purities greater than 99% wt. were recovered. experimental information about reaction and crystallization kinetics was used to developed models. Such models were used to design model-based optimizations in which the productivity of the operation was enhanced by selecting an optimal temperature profile.
The second example is a reactive crystallization towards the manufacture of β-lactam antibiotics. One of the major drawbacks of the utilization of enzymes towards the manufacture of β-lactam antibiotics is the fact that the same enzyme that catalyzes the synthesis of the antibiotic also catalyzes its hydrolysis and thus, its degradation. The reaction scheme is a kinetically controlled synthesis in which the desired product is an intermediate within the network. Hence, the focus of this work is to design an efficient reactive crystallization in which the product is crystallized before it is consumed by hydrolysis. In order to accomplish this goal we have study solution equilibria, reaction kinetics, and crystallization kinetics. Even though crystallization kinetics of ampicillin has been previously reported; the reported models are not applicable to a reactive crystallization scheme for a variety of reasons. In this work, we have developed a robust model that can be applied to multiple crystallization protocols that are consistent with the conditions at which the enzymatic reaction can be performed.
Finally, a reactive-crystallization scheme in which ampicillin was successfully recovered from solution was developed. In this work, crystal seeds were used to promote crystallization of the desired product from the complex media. The results indicated that is possible to perform the reaction and crystallization in parallel, and still recover crystals with high purity. This work is the first example in which ampicillin was produced and recovered with high purity in a single stage. Previous work on…
Advisors/Committee Members: Rousseau, Ronald W. (advisor), Bommarius, Andreas S. (committee member), Kawajiri, Yoshiaki (committee member), Realff, Matthew J. (committee member), Liotta, Charles (committee member).
Subjects/Keywords: Crystallization; Reactive-crystallization; Enantiomers; Antibiotics
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APA (6th Edition):
Encarnacion-Gomez, L. G. (2015). Design and operation of enzymatic reactive crystallization: Applications in chiral purity and kinetically controlled synthesis. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/54322
Chicago Manual of Style (16th Edition):
Encarnacion-Gomez, Luis G. “Design and operation of enzymatic reactive crystallization: Applications in chiral purity and kinetically controlled synthesis.” 2015. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/54322.
MLA Handbook (7th Edition):
Encarnacion-Gomez, Luis G. “Design and operation of enzymatic reactive crystallization: Applications in chiral purity and kinetically controlled synthesis.” 2015. Web. 06 Mar 2021.
Vancouver:
Encarnacion-Gomez LG. Design and operation of enzymatic reactive crystallization: Applications in chiral purity and kinetically controlled synthesis. [Internet] [Doctoral dissertation]. Georgia Tech; 2015. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/54322.
Council of Science Editors:
Encarnacion-Gomez LG. Design and operation of enzymatic reactive crystallization: Applications in chiral purity and kinetically controlled synthesis. [Doctoral Dissertation]. Georgia Tech; 2015. Available from: http://hdl.handle.net/1853/54322
Georgia Tech
10.
Kang, Yuzhi.
Biomass pretreatment toward efficient hydrolysis for sustainable biofuel applications.
Degree: PhD, Chemical and Biomolecular Engineering, 2015, Georgia Tech
URL: http://hdl.handle.net/1853/54852
► The production of biofuels from non-edible plant biomass has been necessitated by the concern for the environmental consequences of fossil fuel use and the tightening…
(more)
▼ The production of biofuels from non-edible plant biomass has been necessitated by the concern for the environmental consequences of fossil fuel use and the tightening of supply and demand for liquid fuels. In contrast to first generation biofuels which rely on crops used for food supplies, second generation biofuels, derived from lignin-containing feedstocks, completely eliminate the competition for food. The major challenges associated with second generation biofuels are both technical and economic. Due to the recalcitrant nature of the raw biomass materials to further biological conversion, their structural degradation often requires severe and costly pretreatment processes such as heat, physical and chemical treatments to disturb and fractionate the biomass. Significant research effort has been devoted to understanding the recalcitrant nature and to accelerate the commercialization process of second generation biofuels. In this thesis, three pretreatment methods that belong to different categories have been investigated to understand their impacts on cellulose and/or lignocellulose and the subsequent hydrolysis steps.
Physicochemical pretreatments, such as steam explosion, have been identified as one of the most effective and cost-efficient pretreatment methods for lignocelluosic materials. In Chapter 2, SO2-catalyzed steam explosion will be discussed and the effect of pretreatment severity on the substrate characteristics and degradation efficiency is also elucidated. Although the crystallinity index (CrI) of cellulose decreases as the severity increases, significant non-specific degradation and low yield of cellulose was observed at high severity. A new method for cellulose CrI determination has been developed with least squares curve fitting and validated with mechanically mixed cellulose samples. Biological pretreatment is another pathway through which the biomass structure can be modified to obtain a more amenable state for enzymatic degradation. Cellulose-binding domain (CBD) originated from Trichoderma reesei Cel7A (i.e. Tr cellobiohydrolase I) has been discovered as a potential biological pretreatment agent which is capable of modifying cellulose crystal structure. An extensive study on the protein engineering, expression, purification and functionalities of Cel7A CBDs was carried out (Chapter 3). The target mutations were identified with a computational protein engineering method involving principal component analysis (PCA). Due to the lack of catalytic activity and high throughput screening method, the library size was limited to nine. The wild-type and mutated CBDs were compared for their adsorption behavior and decrystallization effect on cellulose. Resulting saccharification efficiency after CBD pretreatment were studied and a possible explanation for the rate enhancement was proposed.
In addition to physicochemical and biological pretreatment methods, chemical pretreatment is also a commonly employed method to overcome the recalcitrance of lignocellulosic materials. The most widely studied…
Advisors/Committee Members: Bommarius, Andreas S. (advisor), Realff, Matthew J. (advisor), Lee, Jay H. (committee member), Peralta-Yahya, Pamela (committee member), Doran-Peterson, Joy (committee member).
Subjects/Keywords: Biofuels; Pretreatment
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APA (6th Edition):
Kang, Y. (2015). Biomass pretreatment toward efficient hydrolysis for sustainable biofuel applications. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/54852
Chicago Manual of Style (16th Edition):
Kang, Yuzhi. “Biomass pretreatment toward efficient hydrolysis for sustainable biofuel applications.” 2015. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/54852.
MLA Handbook (7th Edition):
Kang, Yuzhi. “Biomass pretreatment toward efficient hydrolysis for sustainable biofuel applications.” 2015. Web. 06 Mar 2021.
Vancouver:
Kang Y. Biomass pretreatment toward efficient hydrolysis for sustainable biofuel applications. [Internet] [Doctoral dissertation]. Georgia Tech; 2015. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/54852.
Council of Science Editors:
Kang Y. Biomass pretreatment toward efficient hydrolysis for sustainable biofuel applications. [Doctoral Dissertation]. Georgia Tech; 2015. Available from: http://hdl.handle.net/1853/54852
Georgia Tech
11.
Park, Won Min.
Self-assembly of protein-based suprastructures.
Degree: PhD, Chemical and Biomolecular Engineering, 2015, Georgia Tech
URL: http://hdl.handle.net/1853/58135
► Strategies for self-assembly of protein-based suprastructures were developed. Recombinant protein building blocks were designed, produced, and self-assembled into various suprastructures, which include spheres, vesicles, nanosheets…
(more)
▼ Strategies for self-assembly of protein-based suprastructures were developed. Recombinant protein building blocks were designed, produced, and self-assembled into various suprastructures, which include spheres, vesicles, nanosheets and porous particles. Morphology was manipulated by engineering protein building blocks, controlling self-assembly processes, and combining inorganic nanocrystals into hybrid materials. Self-assembly of spherical protein coacervates was achieved in the extracellular matrix, mediated by spontaneous diffusion-coacervation and high-affinity binding of building blocks. Vesicles and two-dimensional nanosheets were self-assembled from recombinant protein complexes, whose molecular geometry dictated the morphologies of self-assembled structures. Self-clustering hybrid flower-shaped nanoparticles were prepared and further assembled into hierarchically structured porous supraparticles. All the suprastructures were created as modular systems which enabled incorporation folded functional proteins. Enzymes incorporated in the porous supraparticles showed enhanced inactivation of a pro-inflammatory cytokine, tumor necrosis factor-α. The modular design approach, combined with manipulation of morphology, offer opportunities for practical applications.
Advisors/Committee Members: Champion, Julie A. (advisor), Babensee, Julia E. (committee member), Behrens, Sven H. (committee member), Bommarius, Andreas S. (committee member), Sambanis, Athanassios (committee member).
Subjects/Keywords: Protein; Self-assembly
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APA ·
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APA (6th Edition):
Park, W. M. (2015). Self-assembly of protein-based suprastructures. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/58135
Chicago Manual of Style (16th Edition):
Park, Won Min. “Self-assembly of protein-based suprastructures.” 2015. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/58135.
MLA Handbook (7th Edition):
Park, Won Min. “Self-assembly of protein-based suprastructures.” 2015. Web. 06 Mar 2021.
Vancouver:
Park WM. Self-assembly of protein-based suprastructures. [Internet] [Doctoral dissertation]. Georgia Tech; 2015. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/58135.
Council of Science Editors:
Park WM. Self-assembly of protein-based suprastructures. [Doctoral Dissertation]. Georgia Tech; 2015. Available from: http://hdl.handle.net/1853/58135
Georgia Tech
12.
Rose, Harrison B.
Towards an enzymatic route to 2,5-furandicarboxylic acid.
Degree: PhD, Chemical and Biomolecular Engineering, 2018, Georgia Tech
URL: http://hdl.handle.net/1853/61151
► This research project explored the selection and development of an enzymatic route from the renewable feedstocks furfural and carbon dioxide to 2,5-furandicarboxylic acid, a building…
(more)
▼ This research project explored the selection and development of an enzymatic route from the renewable feedstocks furfural and carbon dioxide to 2,5-furandicarboxylic acid, a building block for bio-based polyesters. A putative prenylated flavin-dependent reversible decarboxylase was identified as the most reasonable biocatalyst choice, although it was not isolated in a stable and active form in this work. To support future reaction engineering endeavors, this project also included studies of the aqueous liquid and solid solubility relationships between the reactive pathway intermediates and possible side products: furfural, 2 furancarboxylic acid, 5-formyl-2-furancarboxylic acid, and 2,5-furandicarboxylic acid. Finally, this work included an exploration into the mathematics of pH equilibria in aqueous reaction systems. These mathematical techniques were used to develop tools for assessing such systems by both colorimetric and calorimetric methods.
Advisors/Committee Members: Bommarius, Andreas S. (advisor), Realff, Matthew J. (committee member), Jones, Christopher W. (committee member), Finn, M. G. (committee member), Sadowski, Gabriele (committee member).
Subjects/Keywords: 2,5-furandicarboxylic acid; pH equilibria; Biocatalysis
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APA (6th Edition):
Rose, H. B. (2018). Towards an enzymatic route to 2,5-furandicarboxylic acid. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/61151
Chicago Manual of Style (16th Edition):
Rose, Harrison B. “Towards an enzymatic route to 2,5-furandicarboxylic acid.” 2018. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/61151.
MLA Handbook (7th Edition):
Rose, Harrison B. “Towards an enzymatic route to 2,5-furandicarboxylic acid.” 2018. Web. 06 Mar 2021.
Vancouver:
Rose HB. Towards an enzymatic route to 2,5-furandicarboxylic acid. [Internet] [Doctoral dissertation]. Georgia Tech; 2018. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/61151.
Council of Science Editors:
Rose HB. Towards an enzymatic route to 2,5-furandicarboxylic acid. [Doctoral Dissertation]. Georgia Tech; 2018. Available from: http://hdl.handle.net/1853/61151
Georgia Tech
13.
Mcdonald, Matthew Alexander.
Continuous manufacturing of beta-lactam antibiotics by enzymatic reactive crystallization.
Degree: PhD, Chemical and Biomolecular Engineering, 2020, Georgia Tech
URL: http://hdl.handle.net/1853/64110
► The enzymatic production of beta-lactam antibiotics can be simplified by integrating the synthesis and separation of the antibiotic within a single vessel. In situ crystallization…
(more)
▼ The enzymatic production of beta-lactam antibiotics can be simplified by integrating the synthesis and separation of the antibiotic within a single vessel. In situ crystallization during the synthesis of beta-lactam antibiotics improves yields by protecting the antibiotic, an intermediate in the enzyme catalyzed reaction pathway, from degradation by the enzyme. The design of a continuous synthesis, crystallization, and isolation (CSCI) process follows naturally because the reaction and crystallization kinetics are already coupled in the batch process. Rather than individually design and size several unit operations for use in series, a single unit that performs several operations at once was developed. The benefits of continuous reactive crystallization include simplified process control, improved environmental sustainability, and increased process performance. Enzyme catalysis decreases process mass intensity and increases reaction selectivity compared to chemical routes to beta-lactams. Use of process analytical technology (PAT) enables real time monitoring of critical process parameters (CPPs) to ensure production of pharmaceutical quality material. The kinetics of the enzyme reactions and antibiotic crystallization were determined in batch for ampicillin and cephalexin. A model of reactive crystallization was built and used to determine the optimal process configuration for continuous production of amoxicillin and cephalexin. Finally, implementation of the continuous process in the lab was begun. This process will enable more sustainable production of beta-lactam antibiotics with potential for on-demand production, especially important in light of recent drug shortages due to the 2020 SARS-CoV-2 pandemic.
Advisors/Committee Members: Bommarius, Andreas S (advisor), Grover, Martha A (advisor), Rousseau, Ronald W (advisor), Brettmann, Blair K (committee member), Lieberman, Raquel L (committee member).
Subjects/Keywords: Crystallization; beta-lactam antibiotics; Continuous manufacturing; penicillin G acylase
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APA (6th Edition):
Mcdonald, M. A. (2020). Continuous manufacturing of beta-lactam antibiotics by enzymatic reactive crystallization. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/64110
Chicago Manual of Style (16th Edition):
Mcdonald, Matthew Alexander. “Continuous manufacturing of beta-lactam antibiotics by enzymatic reactive crystallization.” 2020. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/64110.
MLA Handbook (7th Edition):
Mcdonald, Matthew Alexander. “Continuous manufacturing of beta-lactam antibiotics by enzymatic reactive crystallization.” 2020. Web. 06 Mar 2021.
Vancouver:
Mcdonald MA. Continuous manufacturing of beta-lactam antibiotics by enzymatic reactive crystallization. [Internet] [Doctoral dissertation]. Georgia Tech; 2020. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/64110.
Council of Science Editors:
Mcdonald MA. Continuous manufacturing of beta-lactam antibiotics by enzymatic reactive crystallization. [Doctoral Dissertation]. Georgia Tech; 2020. Available from: http://hdl.handle.net/1853/64110
14.
Clairmont, Ryan Michael.
Azolium ions: A versatile framework for chemistry on early earth.
Degree: PhD, Chemical and Biomolecular Engineering, 2016, Georgia Tech
URL: http://hdl.handle.net/1853/55021
► This work examines azolium catalysis of the small molecules formaldehyde and glyoxylic acid to yield product sugars as the starting point for synthesis of new…
(more)
▼ This work examines azolium catalysis of the small molecules formaldehyde and glyoxylic acid to yield product sugars as the starting point for synthesis of new azolium catalysts. It is broken into two projects: the first focusing on developing a proof of concept process to couple the two reactions, and the second expanding the reaction space using different solvents and catalyst. From these projects, a model for chemical evolution of small molecule catalysts was proposed. Reaction stoichiometry suggests that the process displays autocatalysis; however, the reactions were conducted separately so that kinetic enhancement was not observed. Even without kinetic enhancement, the findings indicate that synthesis of new catalyst from formaldehyde as the sole carbon source is possible, and that the process is robust due to effects such as catalyst deactivation or other loss pathways over time. Alternative work using glyoxylic acid demonstrated that the kinetics for carbohydrate synthesis are much slower.
Advisors/Committee Members: Bommarius, Andreas S. (advisor), Liotta, Charles L. (advisor), Schork, Francis J. (advisor), Grover, Martha (advisor), Weber, Arthur (advisor).
Subjects/Keywords: Azolium; Autocatalysis; Prebiotic
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APA (6th Edition):
Clairmont, R. M. (2016). Azolium ions: A versatile framework for chemistry on early earth. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/55021
Chicago Manual of Style (16th Edition):
Clairmont, Ryan Michael. “Azolium ions: A versatile framework for chemistry on early earth.” 2016. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/55021.
MLA Handbook (7th Edition):
Clairmont, Ryan Michael. “Azolium ions: A versatile framework for chemistry on early earth.” 2016. Web. 06 Mar 2021.
Vancouver:
Clairmont RM. Azolium ions: A versatile framework for chemistry on early earth. [Internet] [Doctoral dissertation]. Georgia Tech; 2016. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/55021.
Council of Science Editors:
Clairmont RM. Azolium ions: A versatile framework for chemistry on early earth. [Doctoral Dissertation]. Georgia Tech; 2016. Available from: http://hdl.handle.net/1853/55021
Georgia Tech
15.
Ichikawa, Hiroyuki.
Biosynthesis of the thiopetins and identification of an F420H2-dependent dehydropiperidine reductase.
Degree: PhD, Chemistry and Biochemistry, 2019, Georgia Tech
URL: http://hdl.handle.net/1853/62709
► Thiopeptins are highly decorated thiopeptide antibiotics similar in structure to thiostrepton A and harbor two unusual features. All thiopeptins contain a thioamide, a rare moiety…
(more)
▼ Thiopeptins are highly decorated thiopeptide antibiotics similar in structure to thiostrepton A and harbor two unusual features. All thiopeptins contain a thioamide, a rare moiety among natural products, and a subset of thiopeptins present with a piperidine in the core macrocycle rather than the more oxidated dehydropiperidine or pyridine rings typically observed in the thiopeptides. Here, we report the identification of the thiopeptin biosynthetic gene (tpn) cluster in Streptomyces tateyamensis and the gene products, TpnLMNW. TpnW shows sequence similarity to transaminases and is likely involved in the biosynthesis of the 4-(1-hydroxyethyl)quinoline-2-carboxylic acid (HEQ) moiety of thiopeptin. HEQ is derived from L-tryptophan and the second step of HEQ biosynthesis requires a transaminase that catalyzes the conversion of 2-methyl-L-tryptophan to 3-(2-methylindolyl)pyruvate. In vitro reconstitution of TpnW activity confirmed that this enzyme is a 2-methyl-L-tryptophan aminotransferase. TpnW is able to utilize 3 indolylpyruvate, p-hydroxyphenylpyruvate, and phenylpyruvate as α-keto acid acceptors but not pyruvate, oxaloacetate, or α-ketoglutarate. TpnMN share homology to YcaO and TfuA proteins, respectively, responsible for thioamidation of peptidic substrates. Heterologous expression of TpnMN in the thiostrepton A producer, Streptomyces laurentii (
S. laurentii), led to the production of a metabolite with a mass matching a thioamidated thiostrepton A. Structural characterization of this metabolite is required to determine if it contains a thioamide suggested by the proposed functions of TpnMN. TpnL shows sequence similarity to (deaza)flavin-dependent oxidoreductases. Heterologous expression of TpnL in the thiostrepton A producer,
S. laurentii, led to the production of a piperidine-containing analog. Binding studies revealed TpnL preferentially binds the deazaflavin cofactor, coenzyme F420, and in vitro reconstitution of TpnL activity confirmed that this enzyme is an F420H2-dependent dehydropiperidine reductase. The identification of TpnL and its activity establishes the basis for the piperidine-containing series a thiopeptides, one of the five main structural groups of this diverse family of antibiotics. This work was published in J. Am. Chem. Soc. in 2018.
Advisors/Committee Members: Kelly, Wendy L. (advisor), Bommarius, Andreas S. (committee member), Kubanek, Julia M. (committee member), Lobachev, Kirill S. (committee member), Oyelere, Adegboyega K. (committee member).
Subjects/Keywords: Biosynthesis thiopeptide
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APA (6th Edition):
Ichikawa, H. (2019). Biosynthesis of the thiopetins and identification of an F420H2-dependent dehydropiperidine reductase. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/62709
Chicago Manual of Style (16th Edition):
Ichikawa, Hiroyuki. “Biosynthesis of the thiopetins and identification of an F420H2-dependent dehydropiperidine reductase.” 2019. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/62709.
MLA Handbook (7th Edition):
Ichikawa, Hiroyuki. “Biosynthesis of the thiopetins and identification of an F420H2-dependent dehydropiperidine reductase.” 2019. Web. 06 Mar 2021.
Vancouver:
Ichikawa H. Biosynthesis of the thiopetins and identification of an F420H2-dependent dehydropiperidine reductase. [Internet] [Doctoral dissertation]. Georgia Tech; 2019. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/62709.
Council of Science Editors:
Ichikawa H. Biosynthesis of the thiopetins and identification of an F420H2-dependent dehydropiperidine reductase. [Doctoral Dissertation]. Georgia Tech; 2019. Available from: http://hdl.handle.net/1853/62709
Georgia Tech
16.
Edens, William Christopher.
Measles and polio vaccination using a microneedle patch to increase vaccination coverage in the developing world.
Degree: PhD, Biomedical Engineering (Joint GT/Emory Department), 2013, Georgia Tech
URL: http://hdl.handle.net/1853/52951
► Despite the existence of effective vaccines for both diseases, measles and poliomyelitis still cause significant worldwide morbidity and mortality. The live-attenuated measles and inactivated polio…
(more)
▼ Despite the existence of effective vaccines for both diseases, measles and poliomyelitis still cause significant worldwide morbidity and mortality. The live-attenuated measles and inactivated polio vaccines are both given using a standard needle and syringe injection. This method of delivery poses many problems for large-scale vaccination campaigns. Microneedles are micron-scale needles which have the potential to overcome many of these hurdles.
In the first study, we showed that the measles vaccine could be successfully incorporated into a solid, metal microneedle system which induced potent neutralizing antibody titers after administration into cotton rats. This response was statistically identical to the same dose delivered using a subcutaneous injection.
The second study focused on enhancing the stability of the measles vaccine after drying and long-term storage. Using a new assay developed from a measles virus variant engineered to encode for green fluorescent protein, it was determined that a combination of sucrose and threonine provided the highest stabilizing effect. Vaccine mixed with this solution retained more than 90% of its activity after 6 months of storage at 4°C and 25°C.
The third study involved the incorporation of the measles vaccine into a dissolving microneedle patch. These patches were used to vaccinate rhesus macaques and the immune response was found to be statistically identical to the same dose delivered by syringe injection. Furthermore, after creation and storage, these patches retained 100% of their infectivity after 2 months at 4°C and 25°C.
The final study attempted to create a dissolving microneedle patch containing a full dose of the inactivated polio vaccine. These patches were then used to deliver a full dose of IPV into the skin of a rhesus macaque. This delivery method produced neutralizing antibody titers to IPV type 1 and 2 that were statistically identical to the same dose delivered using a needle and syringe.
Overall, these studies show that the microneedle patch was a safe, simple and effective method for measles and polio vaccination. This delivery platform has the potential to overcome many of the hurdles that currently stand in the way of measles elimination and polio eradication.
Advisors/Committee Members: Prausnitz, Mark R. (advisor), Bommarius, Andreas S. (committee member), Dixon, J. Brandon (committee member), Kemp, Melissa L. (committee member), Rota, Paul A. (committee member).
Subjects/Keywords: Measles; Microneedle; Polio; Vaccination; Monkey; Skin; Vaccine stability
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APA (6th Edition):
Edens, W. C. (2013). Measles and polio vaccination using a microneedle patch to increase vaccination coverage in the developing world. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/52951
Chicago Manual of Style (16th Edition):
Edens, William Christopher. “Measles and polio vaccination using a microneedle patch to increase vaccination coverage in the developing world.” 2013. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/52951.
MLA Handbook (7th Edition):
Edens, William Christopher. “Measles and polio vaccination using a microneedle patch to increase vaccination coverage in the developing world.” 2013. Web. 06 Mar 2021.
Vancouver:
Edens WC. Measles and polio vaccination using a microneedle patch to increase vaccination coverage in the developing world. [Internet] [Doctoral dissertation]. Georgia Tech; 2013. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/52951.
Council of Science Editors:
Edens WC. Measles and polio vaccination using a microneedle patch to increase vaccination coverage in the developing world. [Doctoral Dissertation]. Georgia Tech; 2013. Available from: http://hdl.handle.net/1853/52951
Georgia Tech
17.
Agrawal, Gaurav.
Systematic optimization and experimental validation of simulated moving bed chromatography systems for ternary separations and equilibrium limited reactions.
Degree: PhD, Chemical and Biomolecular Engineering, 2014, Georgia Tech
URL: http://hdl.handle.net/1853/54028
► Simulated Moving Bed (SMB) chromatography is a separation process where the components are separated due to their varying affinity towards the stationary phase. Over the…
(more)
▼ Simulated Moving Bed (SMB) chromatography is a separation process where the components are separated due to their varying affinity towards the stationary phase. Over the past decade, many modifications have been proposed in SMB chromatography in order to effectively separate a binary mixture. However, the separation of multi-component mixtures using SMB is still one of the major challenges. Although many different strategies have been proposed, previous studies have rarely performed comprehensive investigations for finding the best ternary separation strategy from various possible alternatives. Furthermore, the concept of combining reaction with SMB has been proposed in the past for driving the equilibrium limited reactions to completion by separating the products from the reaction zone. However, the design of such systems is still challenging due to the complex dynamics of simultaneous reaction and adsorption.
The first objective of the study is to find the best ternary separation strategy among various alternatives design of SMB. The performance of several ternary SMB operating schemes, that are proposed in the literature, are compared in terms of the optimal productivity obtained and the amount of solvent consumed. A multi- objective optimization problem is formulated which maximizes the SMB productivity and purity of intermediate eluting component at the same time. Furthermore, the concept of optimizing a superstructure formulation is proposed, where numerous SMB operating schemes can be incorporated into a single formulation. This superstructure approach has a potential to find more advantageous operating scheme compared to existing operating schemes in the literature.
The second objective of the study is to demonstrate the Generalized Full Cycle (GFC) operation experimentally for the first time, and compare its performance to the JO process. A Semba OctaveTM chromatography system is used as an experimental SMB unit to implement the optimal operating schemes. In addition, a simultaneous optimization and model correction (SOMC) scheme is used to resolve the model mismatch in a systematic way. We also show a systematic comparison of both JO and GFC operations by presenting a Pareto plot of the productivity achieved against the desired purity of the intermediate eluting component experimentally.
The third objective of the study is to develop an simulated moving bed reactor (SMBR) process for an industrial-scale application, and demonstrate the potential of the ModiCon operation for improving the performance of the SMBR compared to the conventional operating strategy. A novel industrial application involving the esterification of acetic acid and 1-methoxy-2-propanol is considered to produce propylene glycol methyl ether (PMA) as the product. A multi-objective optimization study is presented to find the best reactive separation strategy for the production of the PMA product. We also present a Pareto plot that compares the ModiCon operation, which allows periodical change of the feed composition and the…
Advisors/Committee Members: Kawajiri, Yoshiaki (advisor), Realff, Matthew J. (committee member), Grover, Martha (committee member), Nenes, Athanasios (committee member), Bommarius, Andreas S. (committee member), Tsiotras, Panagiotis (committee member).
Subjects/Keywords: Simulated moving bed chromatography; Reactive separation; Parameter estimation; Modeling and optimization; Ternary separation
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APA ·
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MLA ·
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APA (6th Edition):
Agrawal, G. (2014). Systematic optimization and experimental validation of simulated moving bed chromatography systems for ternary separations and equilibrium limited reactions. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/54028
Chicago Manual of Style (16th Edition):
Agrawal, Gaurav. “Systematic optimization and experimental validation of simulated moving bed chromatography systems for ternary separations and equilibrium limited reactions.” 2014. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/54028.
MLA Handbook (7th Edition):
Agrawal, Gaurav. “Systematic optimization and experimental validation of simulated moving bed chromatography systems for ternary separations and equilibrium limited reactions.” 2014. Web. 06 Mar 2021.
Vancouver:
Agrawal G. Systematic optimization and experimental validation of simulated moving bed chromatography systems for ternary separations and equilibrium limited reactions. [Internet] [Doctoral dissertation]. Georgia Tech; 2014. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/54028.
Council of Science Editors:
Agrawal G. Systematic optimization and experimental validation of simulated moving bed chromatography systems for ternary separations and equilibrium limited reactions. [Doctoral Dissertation]. Georgia Tech; 2014. Available from: http://hdl.handle.net/1853/54028
Georgia Tech
18.
Oh, Jung Min.
Development of reactive chromatography system for equilibrium-limited reactions.
Degree: PhD, Chemical and Biomolecular Engineering, 2016, Georgia Tech
URL: http://hdl.handle.net/1853/56333
► In the present work, an application of reactive chromatography and SMBR using ion exchange resin as a catalyst and adsorbent will be studied, which will…
(more)
▼ In the present work, an application of reactive chromatography and SMBR using ion exchange resin as a catalyst and adsorbent will be studied, which will be a new platform for production of industrial esters. Among numerous esters, this study focuses on the production of propylene glycol methyl ether acetate (DOWANOLTM PMA glycol ether acetate), one of the most commonly used esters with a high industrial demand. DOWANOLTM PMA glycol ether acetate is the second-most used propylene glycol ether with nearly 90% of its use in surface coatings.
Advisors/Committee Members: Kawajiri, Yoshiaki (committee member), Bommarius, Andreas S. (committee member), Koros, William J. (committee member), Walton, Krista S. (committee member), Donaldson, Megan E. (committee member).
Subjects/Keywords: Reactive chromatography; Esterification; Transesterification; Ion exchange resin
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APA (6th Edition):
Oh, J. M. (2016). Development of reactive chromatography system for equilibrium-limited reactions. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/56333
Chicago Manual of Style (16th Edition):
Oh, Jung Min. “Development of reactive chromatography system for equilibrium-limited reactions.” 2016. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/56333.
MLA Handbook (7th Edition):
Oh, Jung Min. “Development of reactive chromatography system for equilibrium-limited reactions.” 2016. Web. 06 Mar 2021.
Vancouver:
Oh JM. Development of reactive chromatography system for equilibrium-limited reactions. [Internet] [Doctoral dissertation]. Georgia Tech; 2016. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/56333.
Council of Science Editors:
Oh JM. Development of reactive chromatography system for equilibrium-limited reactions. [Doctoral Dissertation]. Georgia Tech; 2016. Available from: http://hdl.handle.net/1853/56333
19.
Smith, McKenzie L.
Systematic investigation of protein-metabolite regulatory interactions: methodologies and context.
Degree: PhD, Chemical and Biomolecular Engineering, 2016, Georgia Tech
URL: http://hdl.handle.net/1853/56353
► A systems-level understanding of metabolism will have far-reaching benefits from medicine to ecology to industry, as it will facilitate the comprehensive profiling and prediction of…
(more)
▼ A systems-level understanding of metabolism will have far-reaching benefits from medicine to ecology to industry, as it will facilitate the comprehensive profiling and prediction of metabolic states in organisms of interest. Systematic characterization strategies have thus far been successfully applied at the genomic, transcriptomic, and proteomic levels, but downstream regulatory interactions have remained comparatively underexplored. We believe this is largely due to the wide sensitivity spectrum required to effect a similarly comprehensive study: the binding affinities of known protein-metabolite regulatory pairs span multiple orders of magnitude. The overarching aim of this work was therefore to explore and develop multiple complementary strategies for discovery and characterization of these interactions. An in vitro reaction assay-based pipeline was developed to provide a flexible framework for both the validation of putative regulatory interactions found via other methods, and the discovery of new regulatory interactions over a wide range of binding affinities. Small-molecule microarrays were explored as a potential platform for high-throughput discovery of the stronger range of binding interactions, which work will provide a basis for future development and wide-range implementation of the assay. Additionally, a concurrent metabolomics study of inappetence in spawning salmon yielded insights into the metabolic profile of inappetent versus fed cohorts; these results also provide high-level context for protein- and pathway- level studies. Taken together, these findings provide a methodological framework to increase the efficiency and range of study for protein-metabolite regulatory interactions, as well as lay groundwork for further expansion of that range, ultimately in service of the future development of systems-level metabolic models.
Advisors/Committee Members: Styczynski, Mark P (advisor), Bommarius, Andreas S (committee member), Champion, Julie A (committee member), Fernandez, Facundo M (committee member), Kelly, Wendy L (committee member).
Subjects/Keywords: Allostery; Metabolomics; Systems biology
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APA (6th Edition):
Smith, M. L. (2016). Systematic investigation of protein-metabolite regulatory interactions: methodologies and context. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/56353
Chicago Manual of Style (16th Edition):
Smith, McKenzie L. “Systematic investigation of protein-metabolite regulatory interactions: methodologies and context.” 2016. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/56353.
MLA Handbook (7th Edition):
Smith, McKenzie L. “Systematic investigation of protein-metabolite regulatory interactions: methodologies and context.” 2016. Web. 06 Mar 2021.
Vancouver:
Smith ML. Systematic investigation of protein-metabolite regulatory interactions: methodologies and context. [Internet] [Doctoral dissertation]. Georgia Tech; 2016. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/56353.
Council of Science Editors:
Smith ML. Systematic investigation of protein-metabolite regulatory interactions: methodologies and context. [Doctoral Dissertation]. Georgia Tech; 2016. Available from: http://hdl.handle.net/1853/56353
20.
Rood, Michael K.
Enzyme-activated growth: development of a nuclear receptor based genetic selection system for engineering biocatalysts.
Degree: PhD, Chemistry and Biochemistry, 2014, Georgia Tech
URL: http://hdl.handle.net/1853/53072
► Beyond their physiological roles, nuclear receptors have been exploited for their ability to act as intracellular sensors of small molecules. Accordingly, yeast two- and three-hybrid…
(more)
▼ Beyond their physiological roles, nuclear receptors have been exploited for their ability to act as intracellular sensors of small molecules. Accordingly, yeast two- and three-hybrid systems have been developed, exploiting them to control reporter gene expression. These systems may be used to identify nuclear receptor ligand interaction, or for protein engineering applications, particularly of the nuclear receptor ligand binding domain. In this work, the use of estrogen receptors as sensors for enzyme catalysis is explored, where expression of a reporter gene is induced in the presence of the product from an enzymatic reaction. This system, which we have called enzyme-activated growth, has applications for the engineering of biocatalysts. Biocatalytic routes are currently being explored in industrial applications since they often have financial and environmental benefits over traditional heterogeneous catalysis. Enzyme-activated growth is designed to serve as a system to select for engineered enzymes capable of catalyzing the desired reaction. For this work, a new yeast two-hybrid strain has been developed and characterized to allow for detection of both agonist and antagonist compounds. To increase the sensitivity of this assay, a variant of the estrogen receptor was created through random mutation, which responded to ligand concentrations an order of magnitude lower than the wild type receptor. The five mutations identified in the best variant were previously unknown in the literature and the roles of each of these are investigated, as is the mechanism by which they alter ligand sensitivity. As a proof-of-principle, the enzymatic production of genistein, an estrogenic metabolite from plants, using the enzyme isoflavone synthase, as well as the production of estrogen from testosterone, is explored. Synthesis of genistein from the starting material naringenin in vivo was detected in the yeast two-hybrid strain; however, attempts at pairing this with estrogen receptor activation and cell growth were met with limited success. Lastly, targeting the estrogen receptor with a series of novel anti-cancer therapeutics is explored. These compounds were designed to both bind and (in)activate the estrogen receptor while inhibiting histone deacetylase activity. The (anti-)estrogenic properties were analyzed as well as their potency as histone deacetylase inhibitors. These properties were compared to their anti-proliferative effects against various cancerous and healthy cell lines to determine their potential as selective anti-cancer therapeutics.
Advisors/Committee Members: Hud, Nicholas V. (advisor), Azizi, Bahareh (committee member), Bommarius, Andreas S. (committee member), Marder, Seth R. (committee member), Ortlund, Eric A. (committee member), Williams, Loren D. (committee member).
Subjects/Keywords: Estrogen receptor; Protein engineering; Genetic selection; Biocatalysis; Breast cancer; Nuclear receptors
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APA (6th Edition):
Rood, M. K. (2014). Enzyme-activated growth: development of a nuclear receptor based genetic selection system for engineering biocatalysts. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/53072
Chicago Manual of Style (16th Edition):
Rood, Michael K. “Enzyme-activated growth: development of a nuclear receptor based genetic selection system for engineering biocatalysts.” 2014. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/53072.
MLA Handbook (7th Edition):
Rood, Michael K. “Enzyme-activated growth: development of a nuclear receptor based genetic selection system for engineering biocatalysts.” 2014. Web. 06 Mar 2021.
Vancouver:
Rood MK. Enzyme-activated growth: development of a nuclear receptor based genetic selection system for engineering biocatalysts. [Internet] [Doctoral dissertation]. Georgia Tech; 2014. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/53072.
Council of Science Editors:
Rood MK. Enzyme-activated growth: development of a nuclear receptor based genetic selection system for engineering biocatalysts. [Doctoral Dissertation]. Georgia Tech; 2014. Available from: http://hdl.handle.net/1853/53072
21.
Park, Jonathan Taejoo.
Enzymatic reduction of nitro compounds to amines with nitroreductases.
Degree: PhD, Chemical and Biomolecular Engineering, 2014, Georgia Tech
URL: http://hdl.handle.net/1853/52267
► NRs are enzymes that catalyze the reduction of nitroaromatics to their corresponding nitroso, hydroxylamine, and, in limited cases, amine They have gathered interest in many…
(more)
▼ NRs are enzymes that catalyze the reduction of nitroaromatics to their corresponding nitroso, hydroxylamine, and, in limited cases, amine They have gathered interest in many scientific communities, and are currently actively researched bioremediation and prodrug activation. Here we attempt to utilize them for the purpose of synthesizing substituted aromatic amines that are found in a number of active pharmaceutical ingredients (APIs). As NRs described in the literature have varying product distribution ranges (from those that produce hydroxylamine to others that yield amine) several similar and different NRs were studied for their selectivity. Additionally, a quantitative structure-activity relationship (QSAR) was determined to characterize the substrate specificity of NRs. To employ the use of flavoenzymes in synthesis, multiple reaction- and protein-engineering approaches were devised. One scheme was to establish an enzymo-chemical synthesis where NRs were paired with reducing agents for a chemical reduction. Another method was to create a monomeric NR through directed evolution from ER scaffolds for future immobilization applications. Protein engineering techniques were also utilized on NADH oxidases which we characterized and developed for nicotinamide cofactor regeneration. As a whole, this dissertation expands our current understanding on NRs and demonstrates the possibility of using several flavoenzymes in the synthesis of organic molecules.
Advisors/Committee Members: Bommarius, Andreas S. (advisor), Gadda, Giovanni (committee member), Jones, Christopher W. (committee member), Champion, Julie A. (committee member), Spain, Jim C. (committee member).
Subjects/Keywords: Biocatalysis; Enzyme; Nitroreductase; Active pharmaceutical ingredient; Nitro; Reduction; Protein; Protein engineering
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APA (6th Edition):
Park, J. T. (2014). Enzymatic reduction of nitro compounds to amines with nitroreductases. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/52267
Chicago Manual of Style (16th Edition):
Park, Jonathan Taejoo. “Enzymatic reduction of nitro compounds to amines with nitroreductases.” 2014. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/52267.
MLA Handbook (7th Edition):
Park, Jonathan Taejoo. “Enzymatic reduction of nitro compounds to amines with nitroreductases.” 2014. Web. 06 Mar 2021.
Vancouver:
Park JT. Enzymatic reduction of nitro compounds to amines with nitroreductases. [Internet] [Doctoral dissertation]. Georgia Tech; 2014. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/52267.
Council of Science Editors:
Park JT. Enzymatic reduction of nitro compounds to amines with nitroreductases. [Doctoral Dissertation]. Georgia Tech; 2014. Available from: http://hdl.handle.net/1853/52267
22.
Paye, Mariétou F.
Biocatalysis of amide and peptide bond synthesis by cocaine esterase and α-amino acid ester hydrolase.
Degree: PhD, Chemistry and Biochemistry, 2017, Georgia Tech
URL: http://hdl.handle.net/1853/59218
► Amide and peptide bonds-containing compounds are ubiquitous in Nature and popular in the pharmaceutical and chemical industries. Amide bond synthesis occurs with an un-activated (thermodynamic…
(more)
▼ Amide and peptide bonds-containing compounds are ubiquitous in Nature and popular in the pharmaceutical and chemical industries. Amide bond synthesis occurs with an un-activated (thermodynamic control: carboxylic acid) or activated (kinetic control: carboxylic ester) and an amine an as the starting materials. With the goal to develop an affordable, readily available, and substrate independent assay, a pH-based assay was conceived with phenol red as the dye of choice for studies. In addition to the assay, using the pKa’
s of substrates, products, and buffers as well as the absorbance of dye, a mathematical model was developed to calculate pH and predict, conversion of substrate into the products. The assay was capable of distinguishing synthesis of amide from hydrolysis of ester. Using the assay, substrate and reaction promiscuity of cocaine esterase was explored. Cocaine esterase (CocE) was found to have distinctive properties compared to α-amino acid ester hydrolase (AEH). While AEH is capable of synthesizing β-lactam antibiotics such as ampicillin, CocE is not. While CocE is able to take one of the starting materials of ampicillin synthesis, phenylglycine methyl ester, to synthesize dipeptides, AEH shows no such activity. The preliminary results show that CocE has greater preference for amide synthesis over that of amide hydrolysis. Finally, while AEH only accepts α-amino compounds, CocE has the tendency to polymerize such compounds if they are esters; CocE is also capable of accepting various non-amino acid esters with notable chemical features. CocE prefers aromatic compounds to those with alkyl moieties as leaving groups or acyl moieties. The opposite was found to be true with cases in which the acyl moiety is a β-keto compound. The results add to the concept of enzyme-structure-activity relationship for CocE. More importantly, it begins to lay the foundation from which amide synthesis activity of CocE can be engineered.
Advisors/Committee Members: Finn, M. G. (advisor), Bommarius, Andreas S. (committee member), Kelly, Wendy (committee member), Oyelere, Adegboyega K. (committee member), Williams, Loren (committee member).
Subjects/Keywords: Protein engineering; Beta-lactam antibiotics; Amino acid ester hydrolase; Cocaine esterase; pH colorimetry; pH modeling
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APA (6th Edition):
Paye, M. F. (2017). Biocatalysis of amide and peptide bond synthesis by cocaine esterase and α-amino acid ester hydrolase. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/59218
Chicago Manual of Style (16th Edition):
Paye, Mariétou F. “Biocatalysis of amide and peptide bond synthesis by cocaine esterase and α-amino acid ester hydrolase.” 2017. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/59218.
MLA Handbook (7th Edition):
Paye, Mariétou F. “Biocatalysis of amide and peptide bond synthesis by cocaine esterase and α-amino acid ester hydrolase.” 2017. Web. 06 Mar 2021.
Vancouver:
Paye MF. Biocatalysis of amide and peptide bond synthesis by cocaine esterase and α-amino acid ester hydrolase. [Internet] [Doctoral dissertation]. Georgia Tech; 2017. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/59218.
Council of Science Editors:
Paye MF. Biocatalysis of amide and peptide bond synthesis by cocaine esterase and α-amino acid ester hydrolase. [Doctoral Dissertation]. Georgia Tech; 2017. Available from: http://hdl.handle.net/1853/59218
23.
Sharma, Aditi.
Studies on amyloid aggregation and cross-species prion transmission.
Degree: PhD, Chemical and Biomolecular Engineering, 2018, Georgia Tech
URL: http://hdl.handle.net/1853/61123
► Ordered aggregation of proteins into amyloids (and their transmissible versions, prions) has been shown to result in several neurodegenerative diseases in humans and other mammals.…
(more)
▼ Ordered aggregation of proteins into amyloids (and their transmissible versions, prions) has been shown to result in several neurodegenerative diseases in humans and other mammals. While the effect of ions has been extensively studied in the context of measuring the stability of protein formulations and formation of disordered aggregates, there is limited information available on the effect of ions on the formation of ordered amyloid aggregates. In this thesis, we have investigated in detail the effect of presence of ionic co-solutes on the aggregation of amyloids.
Here, we have studied the efficiency of cross-transmission of the NM fragment of Sup35 prion protein, between three closely related species of the Saccharomyces sensu stricto group. Using anions of the Hofmeister series, we discerned the relative effects of protein sequence, seed conformation, and environment on the cross-species transmission of this protein. Further, through investigation of the aggregation of Amyloid beta-42 (Aβ42) and Sup35NM in the presence of anions we have uncovered interesting differences in their aggregation behavior suggesting key differences in the aggregation mechanism of these proteins. Lastly, we developed a computational model for amyloid aggregation kinetics and used it for global fitting of Sup35NM amyloid aggregation data. In all, this thesis expands the current knowledge of ion-specific effects on aggregation of amyloid proteins as well as of the mechanisms of amyloid aggregation.
Advisors/Committee Members: Bommarius, Andreas S. (advisor), Chernoff, Yury O. (committee member), Behrens, Sven H. (committee member), Champion, Julie A. (committee member), Finn, M. G. (committee member).
Subjects/Keywords: Protein aggregation; Amyloid; Prion; Hofmeister; Species barrier
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APA (6th Edition):
Sharma, A. (2018). Studies on amyloid aggregation and cross-species prion transmission. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/61123
Chicago Manual of Style (16th Edition):
Sharma, Aditi. “Studies on amyloid aggregation and cross-species prion transmission.” 2018. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/61123.
MLA Handbook (7th Edition):
Sharma, Aditi. “Studies on amyloid aggregation and cross-species prion transmission.” 2018. Web. 06 Mar 2021.
Vancouver:
Sharma A. Studies on amyloid aggregation and cross-species prion transmission. [Internet] [Doctoral dissertation]. Georgia Tech; 2018. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/61123.
Council of Science Editors:
Sharma A. Studies on amyloid aggregation and cross-species prion transmission. [Doctoral Dissertation]. Georgia Tech; 2018. Available from: http://hdl.handle.net/1853/61123
24.
Wells, Tyrone.
Lignin for bioenergy & biomaterials.
Degree: PhD, Chemistry and Biochemistry, 2015, Georgia Tech
URL: http://hdl.handle.net/1853/53575
► Sustainable waste treatment and lignin development strategies targeted for biorefineries will benefit industry, consumers, and the environment. This dissertation demonstrates the feasibility of a novel…
(more)
▼ Sustainable waste treatment and lignin development strategies targeted for biorefineries will benefit industry, consumers, and the environment. This dissertation demonstrates the feasibility of a novel biochemical pathway capable of converting sugars and lignin sourced from biorefinery waste streams into microbial oils suitable for biodiesel, cosmetic, and biopharmaceutical applications. This biochemical pathway also presents interesting avenues for the commercial production of higher-value intermediate metabolites such as catechol, protocatechuate, pyruvate, and succinate. Alternatively, this dissertation also demonstrates a unique polymerization strategy for lignin that can be adopted towards the production of green polymeric biomaterials. Overall, these strategies jointly present intriguing routes for lignin valorization.
Advisors/Committee Members: Kubanek, Julia (advisor), Ragauskas, Arthur J. (advisor), Deng, Yulin (committee member), Singh, Preet (committee member), Barry, Bridgette (committee member), Bommarius, Andreas S. (committee member), Bottomley, Lawrence A. (committee member).
Subjects/Keywords: Lignin; Bioenergy; Biomaterials; Biorefinery; Sugars; Fermentation; TGA; NMR; Biochemicals; Green chemistry
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APA (6th Edition):
Wells, T. (2015). Lignin for bioenergy & biomaterials. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/53575
Chicago Manual of Style (16th Edition):
Wells, Tyrone. “Lignin for bioenergy & biomaterials.” 2015. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/53575.
MLA Handbook (7th Edition):
Wells, Tyrone. “Lignin for bioenergy & biomaterials.” 2015. Web. 06 Mar 2021.
Vancouver:
Wells T. Lignin for bioenergy & biomaterials. [Internet] [Doctoral dissertation]. Georgia Tech; 2015. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/53575.
Council of Science Editors:
Wells T. Lignin for bioenergy & biomaterials. [Doctoral Dissertation]. Georgia Tech; 2015. Available from: http://hdl.handle.net/1853/53575
Georgia Tech
25.
Hicks, Tanya Temaca.
Preparation, characterization, and activity of mono-dispersed supported catalysts.
Degree: MS, Chemical Engineering, 2004, Georgia Tech
URL: http://hdl.handle.net/1853/4765
► Mono-dispersed supported Ni catalysts were synthesized using the water-CTAB-hexanol reverse micellar system. The core of the reverse micelles contained an aqueous solution of NiCl2. Dynamic…
(more)
▼ Mono-dispersed supported Ni catalysts were synthesized using the water-CTAB-hexanol reverse micellar system. The core of the reverse micelles contained an aqueous solution of NiCl2. Dynamic light scattering measurements showed that microemulsions having a water-to-surfactant molar ratio, Wo, of 10 lead to reverse micelles with lowest polydispersity, longest stability, and size range of interest. At an oil-to-aqueous phase ratio of 2, the diameter of the reverse micelles was found to increase with Wo in a linear fashion. At higher values of Wo (i.e. 25-30), the polydispersity was found to increase when lowering the amount of surfactant in the system. Ultimately, O/A = 2 and Wo = 10 were chosen as optimal conditions for microemulsion preparation.
The aqueous NiCl2 concentration within the micelles was varied between 0.1 and 0.001 M. DLS results showed that although the average micelle diameter was between 70-83 nm throughout the range of metal salt concentrations, the crystallite size estimate based upon the reported micelle diameter and known aqueous NiCl2 concentration ranged between 2 to 7 nm. Therefore, the Ni crystallite size was varied by changing the aqueous NiCl2 concentration due to instability issues arising when changing the value of Wo.
After deposition onto an alumina mesh support, the particles were dried, calcined, and reduced to produce Ni clusters. SEM and EDS analysis was used to confirm the presence of Ni compounds after the calcination stage. By the varying the aqueous NiCl2 concentration within the micelles, .0039, .0013, and .00039 wt. % Ni catalysts were produced and characterized using SEM. Particles in the size range of 10-14 nm were noticed for the .0039 wt. % Ni catalysts after reduction, 7-11 nm for .0013 wt. % Ni, and 5-9 nm for .00039 wt. % Ni. The lower-end of these particle size ranges was comparable to the crystallite size estimates.
Ethane hydrogenolysis and ethylene hydrogenation reactions were conducted over the emulsion-prepared catalysts in order to determine particle size effects on catalytic activity. Results showed that the catalytic activity, defined in terms of per unit metal surface atom (or TON, turnover number), decreases with increasing particle size for the hydrogenolysis reaction. This trend may be due to an intrinsic size effect in which smaller particles exhibit the chemical or structural properties necessary for achieving a higher reaction rate. The results for ethylene hydrogenation showed that the reaction rate did not significantly change with crystallite size, confirming that the reaction is facile or structure-insensitive.
Advisors/Committee Members: Agrawal, Pradeep K. (advisor), Bommarius, Andreas S. (committee member), Schork, F. Joseph (committee member), Agrawal, Pradeep K. (Committee Chair), Bommarius, Andreas S. (Committee Member), Schork, F. Joseph (Committee Member).
Subjects/Keywords: Microemulsions; Catalysts; Mono-dispersed; Alumina; Reverse micelles
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APA (6th Edition):
Hicks, T. T. (2004). Preparation, characterization, and activity of mono-dispersed supported catalysts. (Masters Thesis). Georgia Tech. Retrieved from http://hdl.handle.net/1853/4765
Chicago Manual of Style (16th Edition):
Hicks, Tanya Temaca. “Preparation, characterization, and activity of mono-dispersed supported catalysts.” 2004. Masters Thesis, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/4765.
MLA Handbook (7th Edition):
Hicks, Tanya Temaca. “Preparation, characterization, and activity of mono-dispersed supported catalysts.” 2004. Web. 06 Mar 2021.
Vancouver:
Hicks TT. Preparation, characterization, and activity of mono-dispersed supported catalysts. [Internet] [Masters thesis]. Georgia Tech; 2004. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/4765.
Council of Science Editors:
Hicks TT. Preparation, characterization, and activity of mono-dispersed supported catalysts. [Masters Thesis]. Georgia Tech; 2004. Available from: http://hdl.handle.net/1853/4765
Georgia Tech
26.
Choi, Jaein.
Algorithmic Framework for Improving Heuristics in Stochastic, Stage-Wise Optimization Problems.
Degree: PhD, Chemical Engineering, 2004, Georgia Tech
URL: http://hdl.handle.net/1853/4954
► Algorithmic Framework for Improving Heuristics in Stochastic, Stage-Wise Optimization Problems Jaein Choi 172 Pages Directed by Dr. Jay H. Lee and Dr. Matthew J. Realff…
(more)
▼ Algorithmic Framework for Improving Heuristics in
Stochastic, Stage-Wise Optimization Problems
Jaein Choi
172 Pages
Directed by Dr. Jay H. Lee and Dr. Matthew J. Realff
The goal of this thesis is the development of a computationally tractable solution method for stochastic, stage-wise optimization problems. In order to achieve the goal, we have developed a novel algorithmic framework based on Dynamic Programming (DP) for improving heuristics. The propose method represents a systematic way to take a family of solutions and patch them together as an improved solution. However, patching is accomplished in state space, rather than in solution space. Since the proposed approach utilizes simulation with heuristics to circumvent the curse of dimensionality of the DP, it is named as Dynamic Programming in Heuristically Restricted State Space. The proposed algorithmic framework is applied to stochastic Resource Constrained Project Scheduling problems, a real-world optimization problem with a high dimensional state space and significant uncertainty equivalent to billions of scenarios. The real-time decision making policy obtained by the proposed approach outperforms the best heuristic applied in simulation stage to form the policy. The proposed approach is extended with the idea of Q-Learning technique, which enables us to build empirical state transition rules through simulation, for stochastic optimization problems with complicated state transition rules. Furthermore, the proposed framework is applied to a stochastic supply chain management problem, which has high dimensional action space as well as high dimensional state space, with a novel concept of implicit sub-action space that efficiently restricts action space for each state in the restricted state space. The resulting real-time policy responds to the time varying demand for products by stitching together decisions made by the heuristics and improves overall performance of the supply chain. The proposed approach can be applied to any problem formulated as a stochastic DP, provided that there are reasonable heuristics available for simulation.
Advisors/Committee Members: Lee, Jay H. (Committee Chair), Realff, Matthew R. (Committee Co-Chair), Ahmed, Shabbir (Committee Member), Ayhan, Hayriye (Committee Member), Bommarius, Andreas S. (Committee Member).
Subjects/Keywords: Scheduling; Uncertainty; Optimization; Heuristics; Supply chain management; Dynamic programming
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APA (6th Edition):
Choi, J. (2004). Algorithmic Framework for Improving Heuristics in Stochastic, Stage-Wise Optimization Problems. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/4954
Chicago Manual of Style (16th Edition):
Choi, Jaein. “Algorithmic Framework for Improving Heuristics in Stochastic, Stage-Wise Optimization Problems.” 2004. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/4954.
MLA Handbook (7th Edition):
Choi, Jaein. “Algorithmic Framework for Improving Heuristics in Stochastic, Stage-Wise Optimization Problems.” 2004. Web. 06 Mar 2021.
Vancouver:
Choi J. Algorithmic Framework for Improving Heuristics in Stochastic, Stage-Wise Optimization Problems. [Internet] [Doctoral dissertation]. Georgia Tech; 2004. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/4954.
Council of Science Editors:
Choi J. Algorithmic Framework for Improving Heuristics in Stochastic, Stage-Wise Optimization Problems. [Doctoral Dissertation]. Georgia Tech; 2004. Available from: http://hdl.handle.net/1853/4954
Georgia Tech
27.
Kothari, Neeraj.
Novel Polarimetry Techniques.
Degree: PhD, Physics, 2007, Georgia Tech
URL: http://hdl.handle.net/1853/19779
► Polarization specific measurements are advancing the capabilities of scientific instruments looking for ever smaller effects and material parameters. For example, the magneto-optical nonlinear Faraday effect…
(more)
▼ Polarization specific measurements are advancing the capabilities of scientific instruments looking for ever smaller effects and material parameters. For example, the magneto-optical nonlinear Faraday effect can be used to characterize various electric and magnetic polarizability parameters of an individual molecule. Another major application is detection of desired particles in a highly scattering environment, the physical effect of which has been extensively researched, and is being overcome by using time-gated and polarization techniques. The polarimeter sensitivity is limited by the extinction-ratio obtained from polarizers. Of available polarizer materials, naturally occurring Calcite crystals provide the best extinction ratios because of their good optical homogeneity and high birefringence. However, there is a need for polarization determination with higher sensitivities, and thus a necessity to find better polarizing materials and methods.
I developed a next-generation polarimeter in an attempt to sensitively detect the second-order Faraday effect, along with a substance
s chirality and Verdet constant. Also, I developed a device uniquely able to sensitively detect chiral signatures in the presence of massive depolarizing scattering. In addition, I begun developing a novel type of polarimeter based on the highly-polarization-sensitive nonlinear-optical process of harmonic generation, whose required crystals can be grown with extremely high quality.
Advisors/Committee Members: Trebino, Rick (Committee Chair), Bommarius, Andreas S. (Committee Co-Chair), Erbil, Ahmet (Committee Member), First, Philip N. (Committee Member), Raman, Chandra (Committee Member).
Subjects/Keywords: Organic; Chirality; Faraday effect; Scattering; Polarimeter; Nonlinear optical processes; Polarimetry; Faraday effect; Chirality; Scattering (Physics); Second harmonic generation
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APA (6th Edition):
Kothari, N. (2007). Novel Polarimetry Techniques. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/19779
Chicago Manual of Style (16th Edition):
Kothari, Neeraj. “Novel Polarimetry Techniques.” 2007. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/19779.
MLA Handbook (7th Edition):
Kothari, Neeraj. “Novel Polarimetry Techniques.” 2007. Web. 06 Mar 2021.
Vancouver:
Kothari N. Novel Polarimetry Techniques. [Internet] [Doctoral dissertation]. Georgia Tech; 2007. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/19779.
Council of Science Editors:
Kothari N. Novel Polarimetry Techniques. [Doctoral Dissertation]. Georgia Tech; 2007. Available from: http://hdl.handle.net/1853/19779
Georgia Tech
28.
Broering, James M.
Quantification of Hofmeister Effects on Enzyme Deactivation and Amyloid Protein Stability.
Degree: PhD, Chemical Engineering, 2006, Georgia Tech
URL: http://hdl.handle.net/1853/14077
► Protein stability plays an important role in a wide variety of settings ranging from industrial processes where proteins are used as biocatalysts to medical settings…
(more)
▼ Protein stability plays an important role in a wide variety of settings ranging from industrial processes where proteins are used as biocatalysts to medical settings where misfolded proteins are implicated in disease. Understanding protein stability will allow design of improved bioprocess and pharmaceutical formulations as well as aid in the development of therapies for protein-based diseases. The effects of dissolved salts on protein kinetic stability are studied here. We find that ion-solvent interactions, characterized by the Jones-Dole B-viscosity coefficient, are strong indicators of salt effects on protein deactivation. This finding is used to develop a model for predicting protein deactivation in salt solutions in terms of two competing processes. Since protein unfolding and aggregation can lead to a number of protein misfolding diseases, we test the applicability of our model for describing salt effects on transthyretin aggregation.
As the factors contributing to protein stability become more understood, the use of enzymes as biocatalyst for industrial process will increase, and the need for enzymes active in a wide range of reaction media will increase. We have developed a process using an enzyme in combination with organic-aqueous tunable solvents (OATS) which allows for monophasic reaction of the enzyme with hypdrophobic substrates. The reaction mixture can be separated into two phases by the addition of carbon dioxide pressure. This separation allows for both convenient recovery of the hydrophobic reaction product from the organic phase as well as recycle of the enzyme in the aqueous phase. Overall reaction conversions of 80% and little enzyme activity loss are observed after six reaction cycles.
Advisors/Committee Members: Bommarius, Andreas S. (Committee Chair), Breedveld, Victor L. (Committee Member), Chernoff, Yury O. (Committee Member), Eckert, Charles A. (Committee Member), Rousseau, Ronald W. (Committee Member).
Subjects/Keywords: Transthyretin; Protein stability; Hofmeister series; Enzyme deactivation; Tunable solvent
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APA ·
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APA (6th Edition):
Broering, J. M. (2006). Quantification of Hofmeister Effects on Enzyme Deactivation and Amyloid Protein Stability. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/14077
Chicago Manual of Style (16th Edition):
Broering, James M. “Quantification of Hofmeister Effects on Enzyme Deactivation and Amyloid Protein Stability.” 2006. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/14077.
MLA Handbook (7th Edition):
Broering, James M. “Quantification of Hofmeister Effects on Enzyme Deactivation and Amyloid Protein Stability.” 2006. Web. 06 Mar 2021.
Vancouver:
Broering JM. Quantification of Hofmeister Effects on Enzyme Deactivation and Amyloid Protein Stability. [Internet] [Doctoral dissertation]. Georgia Tech; 2006. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/14077.
Council of Science Editors:
Broering JM. Quantification of Hofmeister Effects on Enzyme Deactivation and Amyloid Protein Stability. [Doctoral Dissertation]. Georgia Tech; 2006. Available from: http://hdl.handle.net/1853/14077
Georgia Tech
29.
Dubey, Anshul.
Search and Analysis of the Sequence Space of a Protein Using Computational Tools.
Degree: PhD, Chemical Engineering, 2006, Georgia Tech
URL: http://hdl.handle.net/1853/14115
► A new approach to the process of Directed Evolution is proposed, which utilizes different machine learning algorithms. Directed Evolution is a process of improving a…
(more)
▼ A new approach to the process of Directed Evolution is proposed, which utilizes different machine learning algorithms. Directed Evolution is a process of improving a protein for catalytic purposes by introducing random mutations in its sequence to create variants. Through these mutations, Directed Evolution explores the sequence space, which is defined as all the possible sequences for a given number of amino acids. Each variant sequence is divided into one of two classes, positive or negative, according to their activity or stability. By employing machine learning algorithms for feature selection on the sequence of these variants of the protein, attributes or amino acids in its sequence important for the classification into positive or negative, can be identified. Support Vector Machines (SVMs) were utilized to identify the important individual amino acids for any protein, which have to be preserved to maintain its activity. The results for the case of beta-lactamase show that such residues can be identified with high accuracy while using a small number of variant sequences. Another class of machine learning problems, Boolean Learning, was used to extend this approach to identifying interactions between the different amino acids in a proteins sequence using the variant sequences. It was shown through simulations that such interactions can be identified for any protein with a reasonable number of variant sequences. For experimental verification of this approach, two fluorescent proteins, mRFP and DsRed, were used to generate variants, which were screened for fluorescence. Using Boolean Learning, an interacting pair was identified, which was shown to be important for the fluorescence. It was also shown through experiments and simulations that knowing such pairs can increase the fraction active variants in the library. A Boolean Learning algorithm was also developed for this application, which can learn Boolean functions from data in the presence of classification noise.
Advisors/Committee Members: Bommarius, Andreas S. (Committee Co-Chair), Lee, Jay H. (Committee Co-Chair), Realff, Matthew J. (Committee Co-Chair), Borodovsky, Mark (Committee Member), Lutz, Stefan (Committee Member).
Subjects/Keywords: OCAT; Interacting residues of a protein; Important residues of a protein; Boolean learning; Support vector machines; Machine learning; Directed evolution
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CSE |
Export
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APA (6th Edition):
Dubey, A. (2006). Search and Analysis of the Sequence Space of a Protein Using Computational Tools. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/14115
Chicago Manual of Style (16th Edition):
Dubey, Anshul. “Search and Analysis of the Sequence Space of a Protein Using Computational Tools.” 2006. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/14115.
MLA Handbook (7th Edition):
Dubey, Anshul. “Search and Analysis of the Sequence Space of a Protein Using Computational Tools.” 2006. Web. 06 Mar 2021.
Vancouver:
Dubey A. Search and Analysis of the Sequence Space of a Protein Using Computational Tools. [Internet] [Doctoral dissertation]. Georgia Tech; 2006. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/14115.
Council of Science Editors:
Dubey A. Search and Analysis of the Sequence Space of a Protein Using Computational Tools. [Doctoral Dissertation]. Georgia Tech; 2006. Available from: http://hdl.handle.net/1853/14115
Georgia Tech
30.
Lountos, George Themistoclis.
Structural and Mechanistic Insights From High Resolution Crystal Structures of the Toluene-4-Monooxygenase Catalytic Effector Protein, NAD(P)H Oxidase and Choline Oxidase.
Degree: PhD, Chemistry and Biochemistry, 2005, Georgia Tech
URL: http://hdl.handle.net/1853/7633
► X-ray crystallography provides detailed information of the atomic structure of macromolecules that aides in the understanding of their molecular function. In this study, the three-dimensional…
(more)
▼ X-ray crystallography provides detailed information of the atomic structure of macromolecules that aides in the understanding of their molecular function. In this study, the three-dimensional structures of the Toluene-4-monooxygenase catalytic effector protein (T4moD), NAD(P)H oxidase and choline oxidase were determined. The structures of wild-type and two mutant isoforms of T4moD were solved up to 1.7 resolution. Results from the crystallographic studies indicate that there are significant differences between the X-ray structure and the structure previously solved by NMR. The high-resolution structures have helped to define the potential differences in electrostatic surfaces that may govern the feasibility of protein-protein interactions and also reveal a single, well-defined cavity suitable for toluene binding that has substantial different electrostatic properties among the effector protein family members.
The structure of NAD(P)H oxidase from Lactobacillus sanfranciscensis was determined to 1.8 resolution. The flavoenzyme is of considerable interest as it catalyzes the oxidation of two equivalents of NAD(P)H and reduces one equivalent of oxygen to yield two equivalents of water without releasing hydrogen peroxide from the active site. The structure reveals the presence of a redox active cysteine residue that exists as a sulfenic acid and plays an important mechanistic role by reducing hydrogen peroxide to water. Additionally, a tightly bound ADP molecule was discovered in the enzyme which is hypothesized to play an important role in influencing the dual substrate specificity exhibited by the enzyme.
The structure of choline oxidase from Arthrobacter globiformis was solved to 1.86 resolution. Choline oxidase catalyzes the four-electron oxidation of choline to glycine betaine via two sequential FAD-dependent reactions. The structure reveals a cavity within the active site, which is suitable for choline binding. This allows for the identification of the putative binding site for choline and residues involved in substrate-binding and catalysis. Additionally, the structure reveals a highly distorted FAD cofactor that contains a C4a-adduct that is proposed to be either an FAD-C4a-OH or FAD-C4a-O2- complex.
Advisors/Committee Members: Orville, Allen M. (Committee Chair), Bommarius, Andreas S. (Committee Member), Fahrni, Christoph J. (Committee Member), Gadda, Giovanni (Committee Member), Williams, Loren Dean (Committee Member).
Subjects/Keywords: Catalytic effector protein; Flavoenzymes; Oxidases; Cysteine sulfenic acid; Protein crystallography
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APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lountos, G. T. (2005). Structural and Mechanistic Insights From High Resolution Crystal Structures of the Toluene-4-Monooxygenase Catalytic Effector Protein, NAD(P)H Oxidase and Choline Oxidase. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/7633
Chicago Manual of Style (16th Edition):
Lountos, George Themistoclis. “Structural and Mechanistic Insights From High Resolution Crystal Structures of the Toluene-4-Monooxygenase Catalytic Effector Protein, NAD(P)H Oxidase and Choline Oxidase.” 2005. Doctoral Dissertation, Georgia Tech. Accessed March 06, 2021.
http://hdl.handle.net/1853/7633.
MLA Handbook (7th Edition):
Lountos, George Themistoclis. “Structural and Mechanistic Insights From High Resolution Crystal Structures of the Toluene-4-Monooxygenase Catalytic Effector Protein, NAD(P)H Oxidase and Choline Oxidase.” 2005. Web. 06 Mar 2021.
Vancouver:
Lountos GT. Structural and Mechanistic Insights From High Resolution Crystal Structures of the Toluene-4-Monooxygenase Catalytic Effector Protein, NAD(P)H Oxidase and Choline Oxidase. [Internet] [Doctoral dissertation]. Georgia Tech; 2005. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1853/7633.
Council of Science Editors:
Lountos GT. Structural and Mechanistic Insights From High Resolution Crystal Structures of the Toluene-4-Monooxygenase Catalytic Effector Protein, NAD(P)H Oxidase and Choline Oxidase. [Doctoral Dissertation]. Georgia Tech; 2005. Available from: http://hdl.handle.net/1853/7633
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