Bacteriology Commons^™

Preliminary Analyses Of The Diversity Of Soil Microbes On The Campus Of The University Of The Incarnate Word, Viridiana Wheeler

Theses & Dissertations

Soil samples were examined outside Bonilla Science Hall on the campus of the University of the Incarnate Word in San Antonio, Texas, at three time points between the calendar years 2016 and 2017. These time points correspond to Fall, Winter, and Spring. Samples were taken at two topsoil depths, 1 cm and 4 cm, to determine if there is a difference in bacterial load or distribution across the time frame examined.

Soil samples were diluted and plated on nutrient agar plates in order to identify unique colony morphologies. A total of 132 distinct morphological isolates were identified and sequenced. Of …

Lymphoid Hematopoiesis And The Role Of B-Cells In Transgenic Mouse Model Of Sickle Cell Disease, Christina Cotte

University Scholar Projects

Sickle cell disease (SCD) has been shown to be associated with decreased baseline immunity and thus increased susceptibility to infection. I sought to discern possible causes of this by looking into the correlations between SCD and hematopoiesis, the immune system and the neuroendocrine system, and ultimately by conducting experiments surrounding the impaired immune system of SCD. These experiments focused on the potential causes and effects of the diminution of B-1a cells in the SCD spleen. Adoptive transfers, infections with Streptococcus pneumoniae, and histologic imaging were conducted to establish if the diminution of the B-1a cells in the SCD spleen …

Determination Of The Effects That A Previously Uncharacterized Secreted Product From Klebsiella Pneumoniae Has On Citrobacter Freundii And Enterobacter Cloacae Biofilms, Cody M. Hastings

Undergraduate Honors Theses

More so than ever, Multiple Drug Resistant (MDR) bacteria are on the rise due to overuse of antibiotics along with natural selection for adaptations that enhance drug-resistant properties. One particular bacterial family, Enterobacteriaceae, has been problematic, exhibiting several bacterial members that have developed a precipitous resistance to modern antibiotics and are also primary causative agents of nosocomial, or hospital acquired, infections. Citrobacter freundii (CF) and Enterobacter cloacae (ECL) are two species of the Enterobacteriaceae family causing significant medical concern due to their role in producing numerous opportunistic infections such as bacteremia, lower respiratory tract infections, urinary tract infections, and endocarditis. …

Molecular Subtyping Of Staphylococcus Aureus Isolates From The U.P. Community For The Presence Of Toxin-Encoding Genes, Carol I. Kessel

All NMU Master's Theses

Staphylococcus aureus is the most common cause of human bacterial infections; however, humans can also be asymptomatically colonized with S. aureus. Asymptomatic carriers can potentially spread S. aureus infection to others. These infections can range from mild to severe. The pathology of a S. aureus infection is often dependent on which toxins are expressed and the virulence factors with which they are associated. One goal of this study was to isolate S. aureus from healthy, consenting adult volunteers who submitted nasal swabs for culture and qRT-PCR analysis to determine which strains are present in the community. This knowledge could …

Cloning And Expression Of C-Terminal Fragment Of Tonb From Rhizobium Leguminosarum Atcc 14479, Brooke E. Baxter

Undergraduate Honors Theses

The TonB-ExbB-ExbD complex is essential for the siderophore mediated acquisition of iron by Gram negative bacteria. The system provides energy from the proton motive force to the outer membrane in order for the iron siderophore complex to enter into the cell. The main protein involved in energy transduction, TonB, has been extensively studied in the species Escherichia Coli. It has been determined that the protein consists of 239 amino acids. In comparison, however, the TonB of Rhizobium leguminosarum consists of 457 amino acids with the same conserved regions. What is in question, therefore, is how the additional amino acids …

Borrelia Burgdorferi-Specific Iga In Lyme Disease, Christina D'Arco, Raymond Dattwyler, Paul Arnaboldi

NYMC Faculty Publications

The laboratory diagnosis of Lyme disease is currently dependent on the detection of IgM and IgG antibodies against Borrelia burgdorferi, the causative agent of the disease. The significance of serum IgA against B. burgdorferi remains unclear. The production of intrathecal IgA has been noted in patients with the late Lyme disease manifestation, neuroborreliosis, but production of antigen-specific IgA during early disease has not been evaluated. In the current study, we assessed serum IgA binding to the B. burgdorferi peptide antigens, C6, the target of the FDA-cleared C6 EIA, and FlaB(211-223)-modVlsE(275-291), a peptide containing a Borrelia flagellin epitope linked to a …

Evaluating The Impact Of Post-Translational Modifications By The Secreted Zinc Metalloprotease, Gele, On The Major Autolysin Of E. Faecalis, Atla, And A Stress-Induced Protein, Salb, Emily K. Stinemetz

Dissertations and Theses (Open Access)

AtlA is the major peptidoglycan hydrolase of E. faecalis involved in cell separation of dividing cells. SalB is a secreted stress-induced protein regulated by the CroRS system. In addition, these two proteins also appear to be affected by the virulence factor, gelatinase (GelE). GelE is a secreted zinc metalloprotease known to impact various cellular functions by post- translational modification of protein substrates. The overall objective of this work was to understand how GelE cleavage of secreted proteins, specifically AtlA and SalB, changes their function. Herein, I discovered that GelE modifies both AtlA and SalB. As visualized by Western blot analysis …

Characterization Of The Role Of The Pkm101-Encoded T4ss Outer Membrane Core Complex In Substrate Transfer, Pilus Biogenesis, And Recipient Cell Contact, Jay E. Gordon

Dissertations and Theses (Open Access)

The bacterial type IV secretion systems (T4SS) encoded on the Escherichia coli pKM101 and R388 conjugative plasmids and the Agrobacterium tumefaciens virB operon are composed of 12 subunits arranged in an architecturally similar fashion. Structural studies of the T4SS from R388 (Trw_R388) highlighted the presence of a distinct outer membrane core complex (OMCC) and inner membrane complex (IMC) joined together by a central stalk. This thesis is focused on the development of the pKM101 model system and the role of an OMCC cap region formed by alpha helical antenna projections (AP) found in VirB10 and TraF_pKM101. …

The Making Of A Pathogen: Implications Of Phage Domestication In Acinetobacter Baumannii, Allison Welp

Undergraduate Theses

Mutations and horizontal gene transfer have allowed for rapid evolution of many species of bacteria, allowing them to become more virulent and resistant to antibiotics. As a result of these changes, Acinetobacter baumannii has become one of the most prominent drug-resistant bacteria in hospitals. This nosocomial pathogen is capable of causing a range of infections—from pneumonia to sepsis—and is extremely difficult to eradicate from hospital settings. Despite its current status, this species has not always been apparent in healthcare. The emergence of this organism has been extremely rapid; once an innocuous environmental organism, A. baumannii is now resistant to all …

The Incidence Of Mrsa Infections In The United States: Is A More Comprehensive Tracking System Needed?, Kevin T. Kavanagh, Said Abusalem, Lindsay E. Calderon

EKU Faculty and Staff Scholarship

A review of epidemiological studies on the incidence of MRSA infections overtime was performed along with an analysis of data available for download from Hospital Compare (https://data.medicare.gov/data/hospital-compare). We found the estimations of the incidence of MRSA infections varied widely depending upon the type of population studied, the types of infections captured and in the definitions and terminology used to describe the results. We could not find definitive evidence that the incidence of MRSA infections in U.S. community or facilities is decreasing significantly. Of concern are recent data reported to the National Healthcare Safety Network (NHSN) on MRSA bloodstream infections which …

Enhanced Control Of Mycobacterium Tuberculosis Extrapulmonary Dissemination In Mice By An Arabinomannan-Protein Conjugate Vaccine, R Prados-Rosales, L Carreno, T Cheng, C Blanc, B Weinrick, Aharona Glatman-Freedman, A Casadevall, S Hung, A Tripathi, J Xu, Aharona Glatman-Freedman, W Jacobs Jr., J Chan, S Porcelli, J Achkar, A Casadevall

NYMC Faculty Publications

Currently there are a dozen or so of new vaccine candidates in clinical trials for prevention of tuberculosis (TB) and each formulation attempts to elicit protection by enhancement of cell-mediated immunity (CMI). In contrast, most approved vaccines against other bacterial pathogens are believed to mediate protection by eliciting antibody responses. However, it has been difficult to apply this formula to TB because of the difficulty in reliably eliciting protective antibodies. Here, we developed capsular polysaccharide conjugates by linking mycobacterial capsular arabinomannan (AM) to either Mtb Ag85b or B. anthracis protective antigen (PA). Further, we studied their immunogenicity by ELISA and …

Draft Genome Sequences Of Three Closely Related Isolates Of The Purple Nonsulfur Bacterium Rhodovulum Sulfidophilum, Michael S. Guzman, Beau Mcginley, Natalia Santiago-Merced, Dinesh Gupta, Arpita Bose

Biology Faculty Research

We report here the draft genome sequences of three isolates of Rhodovulum sulfidophilum from a single population that will serve as a model system for understanding genomic traits that underlie metabolic variation within closely related marine purple nonsulfur bacteria in natural microbial communities.

Environmental Changes Turn On The Sinorhizobium Melitloti Exor-Exos/Chvi (Rsi) Host Invasion Switch, Shari N. Walcott

Dissertations, Theses, and Capstone Projects

The free-living Gram-negative soil bacterium, Sinorhizobium meliloti, must switch into its host-invading form in order to infect the root hairs of the host plant, alfalfa (Medicago sativa), and establish a nitrogen-fixing symbiosis. The activation of the switch is believed to occur inside the infection chamber that is formed by curling of the root hairs. It is not fully understood what signals in the environment of the root hairs trigger and infection chamber S. meliloti to switch into a host-invading form since these signals were not extensively examined until now. This switch can be observed directly, due to …

Development Of A Novel Method To Express And Purify Vaccinia Virus Early Transcription Factors A7 And D6 Using Bacteria, Omkar M. Gandbhir

Seton Hall University Dissertations and Theses (ETDs)

The eradication of Smallpox is one of the greatest human achievements. However other poxviruses still exist infecting humans (Molluscum Contagiosum, monkeypox, and Vaccinia) or livestock (cowpox, sheeppox). Though vaccines and anti-virals exist, the side effects are serious, and viral resistance has been detected. The genome amongst poxviruses is highly conserved, early gene promoters maintain a specific critical consensus region that can be targeted for development of novel broad spectrum therapeutics. Using Vaccinia early transcription factors (VETFs) a novel method of expressing and purifying VETF A7 and D6 was developed. A7 and D6 are required for transcription of early genes recruiting …

Microbial Interactions In The Phyllosphere Increase Plant Performance Under Herbivore Biotic Stress, Muhammad Saleem, Nicole Meckes, Zahida H. Pervaiz, Milton B. Traw

Plant and Soil Sciences Faculty Publications

The phyllosphere supports a tremendous diversity of microbes and other organisms. However, little is known about the colonization and survival of pathogenic and beneficial bacteria alone or together in the phyllosphere across the whole plant life-cycle under herbivory, which hinders our ability to understand the role of phyllosphere bacteria on plant performance. We addressed these questions in experiments using four genetically and biogeographically diverse accessions of Arabidopsis thaliana, three ecologically important bacterial strains (Pseudomonas syringae DC3000, Xanthomonas campestris, both pathogens, and Bacillus cereus, plant beneficial) under common garden conditions that included fungus gnats (Bradysia spp.). …

Proteomic Approach For Extracting Cytoplasmic Proteins From Streptococcus Sanguinis Using Mass Spectrometry, Fadi Elrami, Kristina Nelson, Ping Xu

Philips Institute for Oral Health Research Publications

Streptococcus sanguinis is a commensal and early colonizer of oral cavity as well as an opportunistic pathogen of infectious endocarditis. Extracting the soluble proteome of this bacterium provides deep insights about the physiological dynamic changes under different growth and stress conditions, thus defining “proteomic signatures” as targets for therapeutic intervention. In this protocol, we describe an experimentally verified approach to extract maximal cytoplasmic proteins from Streptococcus sanguinis SK36 strain. A combination of procedures was adopted that broke the thick cell wall barrier and minimized denaturation of the intracellular proteome, using optimized buffers and a sonication step. Extracted proteome was quantitated …

Annotation And Identification Of Several Glycerolipid Metabolic Related Ortholog Genes; Mrub_0437, Mrub_1813 And Mrub_2759 In The Organism Meithermus Ruber And Their Predicted Respective Orthologs B3926, B4042 And Bo514 Found In E.Coli., Abdul Rahman Abdul Kader, Dr. Lori R. Scott

Meiothermus ruber Genome Analysis Project

We predict Mrub_0437 encodes the enzyme glycerol kinase (DNA coordinates [417621..419183), which is an intermediary step of the glycerolipid metabolic pathway (KEGG map00561), It catalyzes the conversion of glycerol to sn-Glycerol-3-phosphate. The E. coli K12 MG1655 ortholog is predicted to be b3926.

We predict Mrub_1813 encodes the enzyme diacylglycerol kinase (DNA coordinates [1864659..1865063), which is an intermediary step of the glycerolipid metabolic pathway (KEGG map00561), It catalyzes the conversion of 1,2-diacyl-sn-glycerol to 1,2-diacyl-sn-glycerol 3-phosphate. The E. coli K12 MG1655 ortholog is predicted to be b4042.

We predict Mrub_2759 encodes the enzyme glycerol kinase (DNA coordinates [2799712..2800665), which is an intermediary …

Carbapenem-Resistant Klebsiella Pneumoniae In Barbados: Driving Change In Practice At The National Level., Corey Forde, Bryan Stierman, Pilar Ramon-Pardo, Thais Dos Santos, Nalini Singh

Psychiatry and Behavioral Sciences Faculty Publications

Introduction

Carbapenem-resistant Klebsiella pneumoniae (CRKP) is of growing concern globally. The risk for transmission of antimicrobial resistant organisms across several continents to the Caribbean is a real one given its tourism industry. After a cluster of cases of CRKP were detected, several studies detailed in this report were initiated to better characterize the problem.

Methods

A hospital-wide point prevalence study and active surveillance were performed at Queen Elizabeth Hospital (QEH) in Barbados in 2013 to assess the prevalence of CRKP infection/colonization. Following this, a 1-year longitudinal study measured the prevalence of CRKP isolates in the hospital and across all healthcare …

A Diagnostic And Control Programme For Johne’S Disease On Irish Dairy Farms, Aideen Kennedy

Theses

Johne’s disease (JD) is an enteritis of ruminants with potential zoonotic implications. JD diagnosis and control present difficulties given JDs prolonged subclinical nature. In order to improve JD control in Ireland, PhD aims included conducting a national survey documenting high-risk husbandry practices employed on Irish farms, thereby targeting areas for improved management. Furthermore as JD has been associated with on-farm economic losses internationally, this research programme aimed to analyse production losses associated with testing JD ELISA positive on Irish dairy farms. A longitudinal study was also conducted to assess if successful JD control can be achieved using gold-standard protocols. Due …

In Search Of A Function For An Uncharacterized Conserved Protein In Streptococcus Sanguinis Sk36, Ayana Scott-Elliston

Theses and Dissertations

With the number of fully sequenced bacterial genomes increasing in the past 7 years, it has been discovered that a large percentage of the putative protein coding genes have no known function. This lack of knowledge leaves scientists with an incomplete understanding of bacteria. In this study, conserved hypothetical protein mutants from Streptococcus sanguinis SK36 were screened on solid media with various environmental conditions. From these screens, the candidate protein, SSA_2372, displayed a sensitivity to acidic conditions. Its homolog in Bacillus subtilis 168, BSU00030, also displayed a sensitivity to pH conditions at its acid tolerance extremes unlike its other homolog …