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Full-Text Articles in Molecular Biology

Detection Of Beta-Lactamase Variants In Municipal Wastewater And Fresh Water, Sunil Pandey Jan 2019

Detection Of Beta-Lactamase Variants In Municipal Wastewater And Fresh Water, Sunil Pandey

Masters Theses

The occurrence and spread of antibiotic-resistant genes (ARGs) are pressing public health problems worldwide. A key factor contributing to the spread of ARGs is lateral gene transfer. Wastewater treatment plants (WWTPs) are measured hot spots of microbial diversity and resistance because they receive polluted wastewater from diverse sources and contain a variety of different environments with dense bacterial loads. Due to the overuse of antibiotics the genetic capacities of microbes have profited. This helps every source of resistance gene and every means of horizontal gene transmission to develop the multiple mechanism of resistance to each antibiotic used clinically, agriculturally, or ...


Protein Degradation Regulates Phospholipid Biosynthetic Gene Expression In Saccharomyces Cerevisiae, Bryan Salas-Santiago Jan 2019

Protein Degradation Regulates Phospholipid Biosynthetic Gene Expression In Saccharomyces Cerevisiae, Bryan Salas-Santiago

Doctoral Dissertations

Transcriptional regulation of most phospholipid biosynthetic genes in Saccharomyces cerevisiae is coordinated by inositol and choline. Inositol affects phosphatidic acid (PA) intracellular levels. Opi1p interacts physically with PA and is the main repressor of the phospholipid biosynthetic genes. It is localized in the endoplasmic reticulum (ER) bound to the ER membrane protein Scs2p. When PA levels drop, Opi1p is translocated into the nucleus repressing most phospholipid biosynthetic genes. The OPI1 locus was identified in a screen looking for overproduction and excretion of inositol (Opi-). Opi- mutants are generally associated with a defect in repression of the ...


Nascent Dna Proteomics Analysis Uncovers Dna Replication Dynamics In The Human Pathogen Trypanosoma Brucei, Maria Rocha Granados Jan 2019

Nascent Dna Proteomics Analysis Uncovers Dna Replication Dynamics In The Human Pathogen Trypanosoma Brucei, Maria Rocha Granados

Doctoral Dissertations

DNA is the substrate of many cellular processes including DNA replication, transcription and chromatin remodeling. These processes are coordinated to maintain genome integrity and ensure accurate duplication of genetic and epigenetic information. Genome-wide studies have provided evidence of the relationship between transcription and DNA replication timing. A global analysis of DNA replication initiation in T. brucei showed that TbORC1 (subunit of the origin recognition complex, ORC) binding sites are located at the boundaries of transcription units. Although recent studies in T. brucei indicate functional links among DNA replication and transcription, the underlying mechanisms remain unknown. In this study, we adapted ...


Kinetics Of Hiv-1 Uncoating In C20 Microglial Cells, Melanie Anne Taylor Jan 2019

Kinetics Of Hiv-1 Uncoating In C20 Microglial Cells, Melanie Anne Taylor

MSU Graduate Theses

Uncoating is a poorly understood yet required step of HIV-1 replication that is defined as the disassembly of the viral capsid structure. The goal of this project is to characterize uncoating in C20 microglial cells. These cells are a natural target of HIV-1 that are infected to establish latent viral reservoirs and HIV-associated neurological disorders. A stable C20 cell line that expresses TRIM-CypA was established to study the kinetics of uncoating with the CsA washout assay. The expression of TRIM-CypA was confirmed by western blot and the functionality of the protein was confirmed by a viral infectivity assay. Using this ...


Assessment Of Salmonella Enterica Biofilms And Expression Differences Among Serovars, Zhaohao Shi Dec 2018

Assessment Of Salmonella Enterica Biofilms And Expression Differences Among Serovars, Zhaohao Shi

Theses and Dissertations

Biofilms are communities of microorganisms associated by a matrix of extracellular polymers. In this state, microorganisms occupy an ecological niche distinct from their free-floating, planktonic counterparts. Also, biofilm bacteria become biologically unique as they form communities and lose motility. The acquisition of these physiological attributes enables the biofilm to persist through harsh environmental conditions, including antimicrobial induced stress and to resist sanitization efforts. Because of these features, biofilms can rapidly disseminate across numerous surfaces and as they establish, become challenging to remove. This is a particular issue for the food industry as processing plants offer favorable conditions for biofilm formation ...


Virulence Regulation In Pseudomonas Aeruginosa Via The Alginate Regulators, Algu And Algr, The Posttranscriptional Regulator, Rsma, And The Two-Component System, Algz/R, Sean Stacey Dec 2018

Virulence Regulation In Pseudomonas Aeruginosa Via The Alginate Regulators, Algu And Algr, The Posttranscriptional Regulator, Rsma, And The Two-Component System, Algz/R, Sean Stacey

Electronic Theses and Dissertations

Pseudomonas aeruginosa is a Gram-negative bacillus able to colonize a wide variety of environments. In the human host, P. aeruginosa can establish an acute infection or persist and create a chronic infection. P. aeruginosa is able to establish a niche and persist in human hosts by using a wide array of virulence factors used for: movement, killing host cells, and evading immune cells and antibiotics. Understanding virulence factors and their regulation has proved to be an important means of combating the morbidity and mortality of P. aeruginosa as well as the ever-increasing threat of drug resistance. By targeting virulence factors ...


Host And Viral Molecular Patterns Relevant To Pathogenicity And Immunity, Alexander Christian Stabell Aug 2018

Host And Viral Molecular Patterns Relevant To Pathogenicity And Immunity, Alexander Christian Stabell

Molecular, Cellular, and Developmental Biology Graduate Theses & Dissertations

Patterns in nature, many going unnoticed, are a defining characteristic of life. In this thesis, I will describe four studies that I have completed during my doctoral work. These will highlight how both host immune system and viral pathogens harness non-random biological patterns to aid in immunity or increase pathogenicity, respectively. Chapter 2 will describe the evolutionary history of a component of the primate innate immune system, Schlafen11, and its involvement in the defense against viruses. I attempt to show that Schlafen11 takes advantage of the pattern of non-optimal codon usage of HIV-1 transcripts in order to inhibit viral replication ...


Microbial Ecology Of South Florida Surface Waters: Examining The Potential For Anthropogenic Influences, Chase P. Donnelly Aug 2018

Microbial Ecology Of South Florida Surface Waters: Examining The Potential For Anthropogenic Influences, Chase P. Donnelly

HCNSO Student Theses and Dissertations

South Florida contains one of the largest subtropical wetlands in the world, and yet not much is known about the microbes that live in these surface waters. These microbes play an important role in chemical cycling and maintaining good water quality for both human and ecosystem health. The hydrology of Florida’s surface waters is tightly regulated with the use of canal and levee systems run by the US Army Corps of Engineers and The South Florida Water Management District. These canals run through the Everglades, agriculture, and urban environments to control water levels in Lake Okeechobee, the Water Conservation ...


Transcriptional Silencing And Anti-Silencing Of Virulence Genes In The Bacterial Pathogen Shigella Flexneri: Virb, Dna Supercoiling, And The Histone-Like Nucleoid Structuring Protein, Michael Adam Picker May 2018

Transcriptional Silencing And Anti-Silencing Of Virulence Genes In The Bacterial Pathogen Shigella Flexneri: Virb, Dna Supercoiling, And The Histone-Like Nucleoid Structuring Protein, Michael Adam Picker

UNLV Theses, Dissertations, Professional Papers, and Capstones

Transcriptional silencing and anti-silencing affect many aspects of bacterial physiology, including virulence in bacterial pathogens. In Shigella species, a group of gram-negative pathogens that cause bacillary dysentery in humans, the histone-like nucleoid structuring protein (H-NS) transcriptionally silences virulence genes found on the large virulence plasmid while VirB anti-silences these genes. However, the mechanistic details of their interplay are not fully understood. To elucidate their regulatory mechanisms, I use the icsP virulence locus, which shares a long intergenic region with the divergently transcribed ospZ gene (1535 bp from TSS to TSS). Prior to this work, two discrete H-NS binding regions had ...


Functional Similarity Of Prd-Containing Virulence Regulators In Bacillus Anthracis, Malik Raynor May 2018

Functional Similarity Of Prd-Containing Virulence Regulators In Bacillus Anthracis, Malik Raynor

UT GSBS Dissertations and Theses (Open Access)

Bacillus anthracis produces three regulators, AtxA, AcpA, and AcpB, that control virulence gene expression and are members of an emerging class of regulators termed “PCVRs” (Phosphoenolpyruvate-dependent phosphotransferase regulation Domain-Containing Virulence Regulators). AtxA controls expression of the toxin genes; lef, cya, and pag, and is the master virulence regulator and archetype PCVR. AcpA and AcpB are less well studied. AcpA and AcpB independently positively control transcription of the capsule biosynthetic operon capBCADE, and culture conditions that enhance AtxA activity result in capBCADE transcription in strains lacking acpA and acpB. RNA-Seq was used to assess the regulons of the paralogs in strains ...


Evolution Via Gene Duplication And Alternative Splicing In The Eukaryotic Ski7 And Hbs1 Genes, Alexandra Marshall May 2018

Evolution Via Gene Duplication And Alternative Splicing In The Eukaryotic Ski7 And Hbs1 Genes, Alexandra Marshall

UT GSBS Dissertations and Theses (Open Access)

Gene duplication and alternative splicing are both recognized as important drivers of proteomic diversity and innovation during evolution, but the evolutionary changes over long periods of time or the interrelations of the two processes has not been extensively studied. Here I study these phenomena for the SKI7 and HBS1 gene pair. These Saccharomyces cerevisiae genes were created as part of a whole genome duplication (WGD) event and have since functionally diverged. Although both genes function in mRNA surveillance pathways, the two genes act on different RNAs and have different effects on the target mRNAs. Ski7 brings the Ski complex and ...


Microbiome Of Commercial Broilers Through Evisceration And Immersion Chilling, John A. Handley May 2018

Microbiome Of Commercial Broilers Through Evisceration And Immersion Chilling, John A. Handley

Theses and Dissertations

The United States poultry industry generated 38.6 billion pounds (17,500 metric ton) of meat in 2014 which averaged to 121 pounds (55 kg) per individual of the U.S that same year. Of that meat generated by the poultry industry, an estimated 1 million cases of Salmonellosis will occur. Out of the 1 million cases approximately 40, 000 to 50,000 will be confirmed cases by the CDC. Recently, the USDA has requested changes in the inspection process and are currently allowing processors more freedom to utilize innovation to drive the increase in safer and more desirable foods ...


Optimizing Genetic Manipulation Of Methanogens Through Faster Cloning Techniques, Merrisa Jennings May 2018

Optimizing Genetic Manipulation Of Methanogens Through Faster Cloning Techniques, Merrisa Jennings

Biological and Agricultural Engineering Undergraduate Honors Theses

Methanogenesis is the biological production of methane. Only anaerobic archaea known as methanogens are capable of such a metabolic feat. They have strict living conditions and substrate sources which determine their rate of metabolism. This is of particular importance from a greenhouse gas reduction perspective or biogas capturing perspective. One of the best ways to optimize methanogen methane production is via genetic manipulation. The current procedures are timely though, therefore a faster cloning processes should be developed. The objective of this study was to optimize a premade genetic transformation kit known as the Gibson Kit. The Gibson Kit was supposed ...


The Characterization Of The Transcription Factor Msab And Its Role In Staphylococcal Virulence, Justin Batte Apr 2018

The Characterization Of The Transcription Factor Msab And Its Role In Staphylococcal Virulence, Justin Batte

Dissertations

Staphylococcus aureus is a common human pathogen that is responsible for a wide range of infections, ranging from relative minor skin infections to life-threatening disease such as bacteremia, septicemia, and endocarditis. S. aureus possesses many different virulent factors that aid in its ability to cause this wide array of infections. One major virulence factor includes the production of capsular polysaccharide (CP). The production of CP plays a major role in the virulence response during infection specifically by providing S. aureus an antiphagocytic mechanism that allows the pathogen to evade phagocytosis during an infection. S. aureus has developed complex genetic regulatory ...


Functional And Structural Mimicry Of A-Kinase Anchoring Proteins By Human Adenovirus E1a, Cason R. King Feb 2018

Functional And Structural Mimicry Of A-Kinase Anchoring Proteins By Human Adenovirus E1a, Cason R. King

Electronic Thesis and Dissertation Repository

As an obligate intracellular parasite, human adenovirus (HAdV) must utilize host factors for survival and replication. Early during infection, its multifunctional E1A protein interacts with an impressive range of cellular target proteins to exert control over the cellular environment. Through these virus-host interactions, E1A massively reprograms both viral and cellular transcription to activate the other HAdV genes, downregulate the host’s immune response, and induce the cell cycle. Consequently, E1A converts the infected cell into a compliant state more amenable for HAdV replication, resulting from its numerous protein-protein interactions. I sought to examine E1A’s interaction with cellular protein kinase ...


The Role Of Dynamics Within Bama, The Central Component Of The Bam Complex, Pamela Arden Doerner Barbour Jan 2018

The Role Of Dynamics Within Bama, The Central Component Of The Bam Complex, Pamela Arden Doerner Barbour

Chemistry & Biochemistry Graduate Theses & Dissertations (1986-2018)

BamA is an essential component of the β-­‐barrel assembly machine that folds and inserts outer membrane proteins (OMPs) into the outer membrane of Gram-­‐negative bacteria. BamA is an OMP itself comprised of two domains, a soluble periplasmic N-­‐terminal domain consisting of five polypeptide transport associated (POTRA) repeats and a C-­‐terminal 16-­‐stranded β-­‐barrel domain. The mechanism of BamA is poorly understood but structural data suggests BamA is a dynamic protein with respect to the POTRA domains and barrel. The POTRA domains, numbered 1-5 from the N- to C- termini, can be divided into two sub-domains ...


Relationships Between Factors Influencing Biofilm Formation And Pathogen Retention In Complex Rhizosphere Microbial Communities, Aaron Coristine Jan 2018

Relationships Between Factors Influencing Biofilm Formation And Pathogen Retention In Complex Rhizosphere Microbial Communities, Aaron Coristine

Theses and Dissertations (Comprehensive)

Riparian wetlands are unique habitats facilitating all forms of life. The riverbanks of these environments provide ideal conditions for bacteria, plants, and higher organisms. Of particular interest to this research was the variation in microbial community structure at high, intermediate and poor water quality impacted areas. Assessing the capabilities of plants to retain microbial pathogens was identified. Root systems and corresponding soil are ideal locations for bacterial deposition, resulting in attachment at these areas. Biofilm production in these regions is important for long-term establishment, leading to persistence and potential naturalization. Opportunistic pathogens originating from mammalian fecal matter are introduced into ...


Detection Of The Lung Environment By Multi-Drug Resistant Gram-Negative Bacterial Pathogens, Graham Geier Willsey Jan 2018

Detection Of The Lung Environment By Multi-Drug Resistant Gram-Negative Bacterial Pathogens, Graham Geier Willsey

Graduate College Dissertations and Theses

Nosocomial lung infections are a growing concern in the United States, with more than 300,000 cases reported annually. More than 30 % of which are caused by the Gram-negative bacteria, Pseudomonas aeruginosa and Klebsiella pneumoniae. Similarly, Gram-negative bacteria establish chronic infections in individuals with cystic fibrosis (CF) that are difficult or impossible to eradicate.P. aeruginosa has historically been one of the most prevalent pathogens of adults with CF. However, as antipseudomonal therapy has improved, more antibiotic resistant species have taken hold, including Stenotrophomonas maltophilia, which now colonizes more than 10 % of individuals with CF. Regardless of the cause or ...


Reprogramming The Retina: Next Generation Strategies Of Retinal Neuroprotection And Gene Therapy Vector Potency Assessment, Devin Scott Mcdougald Jan 2018

Reprogramming The Retina: Next Generation Strategies Of Retinal Neuroprotection And Gene Therapy Vector Potency Assessment, Devin Scott Mcdougald

Publicly Accessible Penn Dissertations

Mutations within over 250 known genes are associated with inherited retinal degeneration. Clinical success following gene replacement therapy for Leber’s congenital amaurosis type 2 establishes a platform for the development of downstream treatments targeting other forms of inherited and acquired ocular disease. Unfortunately, several challenges relevant to complex disease pathology and limitations of current gene transfer technologies impede the development of gene replacement for each specific form of retinal degeneration. Here we describe gene augmentation strategies mediated by recombinant AAV vectors that impede retinal degeneration in pre-clinical models of acquired and inherited vision loss. We demonstrate distinct neuroprotective effects ...


All The Right Noises: Causes And Consequences Of Stochastic Trimethylamine Oxide Reductase Expression In Escherichia Coli, Jeffrey Carey Jan 2018

All The Right Noises: Causes And Consequences Of Stochastic Trimethylamine Oxide Reductase Expression In Escherichia Coli, Jeffrey Carey

Publicly Accessible Penn Dissertations

Microbial populations can maximize fitness in dynamic environments through bet hedging, a process wherein a subpopulation assumes a phenotype not optimally adapted to the present environment but well adapted to an environment likely to be encountered. Here we show that oxygen induces fluctuating expression of the trimethylamine oxide (TMAO) respiratory system of Escherichia coli, diversifying the cell population and enabling a bet-hedging strategy that permits growth following oxygen loss. This regulation by oxygen affects the variance in gene expression but leaves the mean unchanged. We show that the oxygen-sensitive transcription factor IscR is the key regulator of variability. Oxygen causes ...


Superresolved Three-Dimensional Analysis Of The Spatial Arrangement Of The Human Immunodeficiency Virus Type-1 (Hiv-1) Envelope Glycoprotein At Sites Of Viral Assembly, Carmen Anne Buttler Jan 2018

Superresolved Three-Dimensional Analysis Of The Spatial Arrangement Of The Human Immunodeficiency Virus Type-1 (Hiv-1) Envelope Glycoprotein At Sites Of Viral Assembly, Carmen Anne Buttler

Electronic Theses and Dissertations

Human Immunodeficiency Virus type 1 (HIV-1) replicates by forcing infected host cells to produce new virus particles, which assemble form protein components on the inner leaflet of the host cell's plasma membrane. This involves incorporation of the essential viral envelope glycoprotein (Env) into a structural lattice of viral Gag proteins. The mechanism of Env recruitment and incorporation is not well understood. To better define this process, we seek to describe the timing of Env-Gag encounters during particle assembly by measuring angular positions of Env proteins about the surfaces of budding particles. Using three-dimensional superresolution microscopy, we show that Env ...


The Role Of The Metallochaperone Hypa In The Acid Survival And Activities Of Nickel Enzymes In Helicobacter Pylori, Heidi Hu Jan 2018

The Role Of The Metallochaperone Hypa In The Acid Survival And Activities Of Nickel Enzymes In Helicobacter Pylori, Heidi Hu

Doctoral Dissertations

Helicobacter pylori is a bacterium that has colonized the human gastric mucosa of over 50% of the world population. Persistent infection can cause gastritis, peptic ulcers, and cancers. The ability of H. pylori to colonize the acidic environment of the human stomach is dependent on the activity of the nickel containing enzymes, urease and NiFe-hydrogenase. The nickel metallochaperone, HypA, was previously shown to be required for the full activity of both enzymes. In addition to a Ni-binding site, HypA also contains a structural Zn site, which has been characterized to alter its averaged structure depending on pH and the presence ...


Biosynthetic Mechanism Of The Antibiotic Capuramycin, Erfu Yan Jan 2018

Biosynthetic Mechanism Of The Antibiotic Capuramycin, Erfu Yan

Theses and Dissertations--Pharmacy

A-102395 is a member of the capuramycin family of antibiotics which was isolated from the culture broth of Amycolatopsis sp. SANK 60206. A-102339 is structurally classified as a nucleoside antibiotic, which like all members of the capuramycin family, inhibits bacterial MraY (translocase I) with IC50 of 11 nM which is the lowest among the capuramycin family. A semisynthetic derivative of capuramycin is currently in clinical trials as an antituberculosis antibiotic, suggesting high potential for using A-102395 as a starting point for new antibiotic discovery. In contrast to other capuramycins, A-102395 has a unique arylamine-containing polyamide side chain. The biosynthetic ...


Emergence Of New Metabolic Pathways In Escherichia Coli, Michael Kristofich Jan 2018

Emergence Of New Metabolic Pathways In Escherichia Coli, Michael Kristofich

Undergraduate Honors Theses

Catalytic promiscuity provides a starting point for the evolution of new enzymes. Taking this concept further, a series of promiscuous enzymes may assemble to form the basis of a new metabolic pathway (termed “serendipitous pathway”) that may emerge and become more efficient in adapting bacterial cells that require it to grow. The Copley lab at the University of Colorado at Boulder has been observing genetic changes that improve growth of Escherichia coli cells that lack the essential gene pdxB. These genetic changes are believed to improve the flux of metabolites through one or more serendipitous pathways that make up for ...


Comparison And Evaluation Of Two Rapid Diagnostic Assays For The Identification Of Mycoplasma Species, Aric James Mcdaniel Jan 2018

Comparison And Evaluation Of Two Rapid Diagnostic Assays For The Identification Of Mycoplasma Species, Aric James Mcdaniel

Graduate Theses and Dissertations

Members of the class Mollicutes are unique among bacteria in that they are unable to synthesize a cell wall. These organisms are also difficult to culture and very slow-growing with some species requiring up to 40 days to culture. Many of these bacteria are also significant pathogens in humans and animals, so rapid identification of isolates is a necessary diagnostic step. Many different tests are used for identification of pathogenic Mollicutes (primarily Mycoplasma and Ureaplasma species), however most tests are not cost or time efficient. Two relatively recent diagnostic tools are matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry and ...


Type Ix Secretion System : Characterization Of An Effector Protein And An Insight Into The Role Of C-Terminal Domain Dimeration In Outer Membrane Translocation., Lahari Koneru Dec 2017

Type Ix Secretion System : Characterization Of An Effector Protein And An Insight Into The Role Of C-Terminal Domain Dimeration In Outer Membrane Translocation., Lahari Koneru

Electronic Theses and Dissertations

Porphyromonas gingivalis and Tannerella forsythia are two of the primary pathogens that are associated in the etiology and progression of chronic periodontitis. In T. forsythia, KLIKK proteases are the recently identified group of proteolytic enzymes that are secreted through Type IX secretion system (T9SS). Among, these KLIKK proteases a synergistic relationship was observed between karilysin and mirolysin in invading the host complement system for the survival of the bacteria. Since, karilysin has been already characterized, in this study we propose to study about mirolysin through structural, biochemical and biological characterization. The obtained results from the experiments has shown the propensity ...


Role Of Incompatibility Group 1 (Inci1) Plasmid-Encoded Factors On Salmonella Enterica Antimicrobial Resistance And Virulence, Pravin Raghunath Kaldhone Dec 2017

Role Of Incompatibility Group 1 (Inci1) Plasmid-Encoded Factors On Salmonella Enterica Antimicrobial Resistance And Virulence, Pravin Raghunath Kaldhone

Theses and Dissertations

Foodborne illnesses are a leading cause of infectious diseases in the world. Among enteric organisms Salmonella is a key pathogen. It’s high prevalence in poultry and other food-animal sources make it imperative to study. Salmonella has the ability to modify its genetic content with help of mobile genetic elements such as plasmids. Incompatibiltiy group 1 (IncI1) plasmids are commonly reported in Salmonella. This study evaluates role on IncI1 plasmids in antimicrobial resistance and virulence in Salmonella. Genetic determinants of resistance and virulence are noted among our IncI1-containing Salmonella isolates. These genetic elements are also transferable and reported to carry ...


Complete Sequencing And Comparative Analysis Of The Genomes Of The First Magnetotactic Gammaproteobacteria Isolated In Pure Culture: Strains Bw-2 And Ss-5, Corey Geurink Dec 2017

Complete Sequencing And Comparative Analysis Of The Genomes Of The First Magnetotactic Gammaproteobacteria Isolated In Pure Culture: Strains Bw-2 And Ss-5, Corey Geurink

UNLV Theses, Dissertations, Professional Papers, and Capstones

The genomes of the first two discovered magnetotactic bacteria (MTB) belonging to the ammaproteobacteria, strains BW-2 and SS-51, were sequenced, sealed, annotated and compared to MTB of other phylogenetic groups. Cells of both strains are rod-shaped and biomineralize cuboctahedral and elongated octahedral crystals of magnetite, respectively, that are enveloped in a protein-embedded, lipid-bilayer membrane referred to as the magnetosome membrane or vesicle. The crystals and their associated membranes are known as magnetosomes. Magnetosome crystals consist of either magnetite (Fe3O4) or greigite (Fe3S4) and, because of their specific mineral compositions, crystal morphologies and sizes, the biomineralization processes involved in magnetosome formation ...


Mechanism Elucidation And Inhibitor Discovery Against Serine And Metallo-Beta-Lactamases Involved In Bacterial Antibiotic Resistance, Orville A. Pemberton Nov 2017

Mechanism Elucidation And Inhibitor Discovery Against Serine And Metallo-Beta-Lactamases Involved In Bacterial Antibiotic Resistance, Orville A. Pemberton

Graduate Theses and Dissertations

The emergence and proliferation of Gram-negative bacteria expressing β-lactamases is a significant threat to human health. β-Lactamases are enzymes that degrade the β-lactam antibiotics (e.g., penicillins, cephalosporins, monobactams, and carbapenems) that we use to treat a diverse range of bacterial infections. Specifically, β-lactamases catalyze a hydrolysis reaction where the β-lactam ring common to all β-lactam antibiotics and responsible for their antibacterial activity, is opened, leaving an inactive drug. There are two groups of β-lactamases: serine enzymes that use an active site serine residue for β-lactam hydrolysis and metalloenzymes that use either one or two zinc ions for catalysis. Serine ...


Cell Division Regulation In Staphylococcus Aureus, Catherine M. Spanoudis Oct 2017

Cell Division Regulation In Staphylococcus Aureus, Catherine M. Spanoudis

Graduate Theses and Dissertations

Cell division is a fundamental biological process that occurs in all kingdoms of life. Our understanding of cell division in bacteria stems from studies in the rod-shaped model organisms: Gram-negative Escherichia coli and Gram-positive Bacillus subtilis. The molecular underpinnings of cell division regulation in non-rod-shaped bacteria remain to be studied in detail. Rod-shaped bacteria possess many positive and negative regulatory proteins that are essential to the proper placement of the division septa and ultimately the production of two identical daughter cells, many of which are absent in cocci. Given that essential cell division proteins are attractive antibacterial drug targets, it ...