Isolation & Characterization Of Bacteria In The Built Environment: Measuring The Effect Of Pharmaceuticals On Growth,
2015
Gettysburg College
Isolation & Characterization Of Bacteria In The Built Environment: Measuring The Effect Of Pharmaceuticals On Growth, Amanda V. Finck, Kelly J. Digeronimo, Nene S. Sy, Zakiya Whatley
Student Publications
This work reports the isolation and characterization of bacteria from the built environment at Gettysburg College in Gettysburg, PA. Surfaces of a water fountain on campus were swabbed and serially streaked to isolate multiple bacteria on R2A agar. Following multiple rounds of growth, the unknown microbial candidates were narrowed to two visiblydistinct organisms. Morphological characterization and phylogenetic identification based on 16S rDNA sequencing revealed that the isolates were Chryseobactierum hispalense and Microbacterium maritypicum. We report synergistic biofilm formation between Chryseobactierum hispalense and Microbacterium maritypicum. The contamination of drinking water with varying levels of personal care products and pharmaceuticals (PCPPs) is …
How Many Particles Are Present In The Air? Bioaerosol Detection Using An Air Particle Counter,
2015
NASA Jet Propulsion Laboratory
How Many Particles Are Present In The Air? Bioaerosol Detection Using An Air Particle Counter, Angie Pamela Rivera, Parag Vaishampayan
STAR Program Research Presentations
Relative cleanliness in terms of particle abundance in spacecraft assembly facilities is determined by particle counts carried out in clean rooms during resting conditions. Particle counters assess total particles and particle size distribution, but do not distinguish inert particles from biological particles, which may include bacterial spores that are resistant to standard cleanroom sterilization procedures. Current cleanroom certifications do not fully assess the effects of human presence on spacecraft contamination since humans are known symbionts to enumerate microorganisms and assessments are performed at rest when there is no human presence. In this study, contamination risks and bioburden in spacecraft assembly …
Collecting Diverse Microorganisms From Rover Spacecraft,
2015
Chicago State University
Collecting Diverse Microorganisms From Rover Spacecraft, Jennifer I. Jacobs, Arianna Jefferson, Heidi Aronson, James Tan, Wayne Schubert, Parag Vaishampayan
STAR Program Research Presentations
. The Planetary Protection discipline at NASA’s Jet Propulsion Laboratory develops and implements procedures to prevent both forward and backward contamination between the Earth and solar system bodies. However, there will always be some microorganisms that will be resistant to the strictest of sterilization methods. In order understand the microorganisms found on spacecraft during assembly, and to rapidly identify them, a mass spectrometry approach was developed. As an experimental approach, a custom database was created for a subset of microorganisms in the Planetary Protection Archive. In order to make the database as accurate and efficient as possible, several different procedures …
Regulation Of Vancomycin Resistance And Stress Response By The Msaabcr Operon In Staphylococcus Aureus,
2015
University of Southern Mississippi
Regulation Of Vancomycin Resistance And Stress Response By The Msaabcr Operon In Staphylococcus Aureus, Dhritiman Samanta
Dissertations
Staphylococcus aureus is the predominant cause of public health problems around the world. Vancomycin has been an important antibiotic against Methicillin Resistant Staphylococcus aureus (MRSA) infections. However, Vancomycin Intermediate S. aureus (VISA) strains have been reported. These strains are characterized by thick cell walls, reduced autolytic rate, reduced PBP4 activity, and increased amount of D-Ala-D-Ala termini in the cell wall. In this study, we show that the msaABCR operon regulates vancomycin resistance in two clinical VISA strains. Deletion of the msaABCR operon in strains Mu50 and HIP6297 resulted in a significant decrease in the minimum inhibitory concentration (MIC) for vancomycin. …
Identification Of Genes Required To Synthesize An Antibiotic-Like Compound From The Soil Bacterium Rhodococcus Sp. Mtm3w5.2,
2015
East Tennessee State University
Identification Of Genes Required To Synthesize An Antibiotic-Like Compound From The Soil Bacterium Rhodococcus Sp. Mtm3w5.2, Amber L. Ward
Electronic Theses and Dissertations
Rhodococcus is a soil bacterium, member of the Actinobacteria, and a close relative of the prolific small molecule producer Streptomyces. Recent interest in Rhodococcus as an under investigated source of possible bioactive secondary metabolites is sparked by the discovery of many polyketide synthase and non-ribosomal peptide synthetase genes of unknown function from sequenced Rhodococcus genomes. Rhodococcus species strain MTM3W5.2 was recently shown to produce a strong inhibitory compound with activity against most strains of Rhodococcus and closely related genera. A goal of this investigation is to discover the gene(s) required to synthesize this inhibitory molecule. The engineered Rhodococcus …
Algr Directly Controls Rsma In Pseudomonas Aeruginosa,
2015
East Tennessee State University
Algr Directly Controls Rsma In Pseudomonas Aeruginosa, Tyler Speaks
Electronic Theses and Dissertations
Pseudomonas aeruginosa is a bacterial pathogen that can infect any human tissue. The lungs of cystic fibrosis patients become chronically infected with Pseudomonas aeruginosa. Virulence factor gene expression is under elaborate regulatory control that remains poorly characterized. Understanding the regulatory hierarchy involved during infection is essential for identifying novel drug targets. RsmA is a post-transcriptional regulatory protein that controls expression of several virulence factors. Previous studies demonstrated alginate regulatory components AlgU and AlgR as regulators of rsmA expression. The aim of this study was to determine how AlgR controls rsmA expression. Western blot analysis of HA-tagged RsmA confirmed lower …
Inhibition Of Cell Differentiation In Bacillus Subtilis By Pseudomonas Protegens,
2015
University of North Carolina at Chapel Hill
Inhibition Of Cell Differentiation In Bacillus Subtilis By Pseudomonas Protegens, Matthew J. Powers, Edgardo Sanabria-Valentín, Albert A. Bowers, Elizabeth A. Shanka
Publications and Research
Interspecies interactions have been described for numerous bacterial systems, leading to the identification of chemical compounds that impact bacterial physiology and differentiation for processes such as biofilm formation. Here, we identified soil microbes that inhibit biofilm formation and sporulation in the common soil bacterium Bacillus subtilis. We did so by creating a reporter strain that fluoresces when the transcription of a biofilm-specific gene is repressed. Using this reporter in a coculture screen, we identified Pseudomonas putida and Pseudomonas protegens as bacteria that secrete compounds that inhibit biofilm gene expression in B. subtilis. The active compound produced by P. protegens was …
Deletion Of Nfnab In Thermoanaerobacterium Saccharolyticum And Its Effect On Metabolism,
2015
Dartmouth College
Deletion Of Nfnab In Thermoanaerobacterium Saccharolyticum And Its Effect On Metabolism, Jonathan Lo, Tianyong Zheng, Daniel G. Olson, Natalie Ruppertsberger, Shital Tripathi, Adam Guss, Lee Lynd
Dartmouth Scholarship
NfnAB catalyzes the reversible transfer of electrons from reduced ferredoxin and NADH to 2 NADP+. The NfnAB complex has been hypothesized to be the main enzyme for ferredoxin oxidization in strains of Thermoanaerobacterium saccharolyticum engineered for increased ethanol production. NfnAB complex activity was detectable in crude cell extracts of T. saccharolyticum. Activity was also detected using activity staining of native PAGE gels. The nfnAB gene was deleted in different strains of T. saccharolyticum to determine its effect on end product formation. In wild-type T. saccharolyticum, deletion of nfnAB resulted in a 46% increase in H2 formation but …
Prokaryotic Diversity In The Rhizosphere Of Organic, Intensive, And Transitional Coffee Farms In Brazil,
2015
San Jose State University
Prokaryotic Diversity In The Rhizosphere Of Organic, Intensive, And Transitional Coffee Farms In Brazil, Adam Caldwell, Livia Silva, Cynthia Da Silva, Cleber Ouverney
Faculty Publications, Biological Sciences
Despite a continuous rise in consumption of coffee over the past 60 years and recent studies showing positive benefits linked to human health, intensive coffee farming practices have been associated with environmental damage, risks to human health, and reductions in biodiversity. In contrast, organic farming has become an increasingly popular alternative, with both environmental and health benefits. This study aimed to characterize and determine the differences in the prokaryotic soil microbiology of three Brazilian coffee farms: one practicing intensive farming, one practicing organic farming, and one undergoing a transition from intensive to organic practices. Soil samples were collected from 20 …
Secretion Of Heat-Labile Enterotoxin By Porcine-Origin Enterotoxigenic Escherichia Coli And Relation To Virulence,
2015
University of Nebraska-Lincoln
Secretion Of Heat-Labile Enterotoxin By Porcine-Origin Enterotoxigenic Escherichia Coli And Relation To Virulence, Prageeth Rukshan Wijemanne
School of Veterinary and Biomedical Sciences: Dissertations, Theses, and Student Research
Heat-labile enterotoxin (LT) is an important virulence factor secreted by some strains of porcine-origin enterotoxigenic Escherichia coli (pETEC). The prototypic human-origin strain H10407 secretes LT via a type II secretion system (T2SS), but its presence or importance in pETEC has not been established. Exposure of pETEC to glucose has been shown to result in different secretion levels of LT. Furthermore, the relationship between the level of LT secreted and the virulence potential of the respective pETEC strain has not been established. To determine the relationship between the capacity to secrete LT and virulence in wild-type (WT) pETEC, 16 strains isolated …
Cofactor Specificity Of The Bifunctional Alcohol And Aldehyde Dehydrogenase (Adhe) In Wild-Type And Mutant Clostridium Thermocellum And Thermoanaerobacterium Saccharolyticum,
2015
Dartmouth College
Cofactor Specificity Of The Bifunctional Alcohol And Aldehyde Dehydrogenase (Adhe) In Wild-Type And Mutant Clostridium Thermocellum And Thermoanaerobacterium Saccharolyticum, Tianyong Zheng, Daniel G. Olson, Liang Tian, Yannick J. Bomble, Michael Himmel, Jonathan Lo, Shuen Hon, A. Joe Shaw, Johannes P. Van Dijken, Lee Lynd
Dartmouth Scholarship
Clostridium thermocellum and Thermoanaerobacterium saccharolyticum are thermophilic bacteria that have been engineered to produce ethanol from the cellulose and hemicellulose fractions of biomass, respectively. Although engineered strains of T. saccharolyticum produce ethanol with a yield of 90% of the theoretical maximum, engineered strains of C. thermocellum produce ethanol at lower yields (∼50% of the theoretical maximum). In the course of engineering these strains, a number of mutations have been discovered in their adhE genes, which encode both alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) enzymes. To understand the effects of these mutations, the adhE genes from six strains of C. …
The C-Terminal Linker Of Ftsz Acts As An Intrinsically Disordered Peptide During Cell Division In Bacillus Subtilis,
2015
Washington University in St Louis
The C-Terminal Linker Of Ftsz Acts As An Intrinsically Disordered Peptide During Cell Division In Bacillus Subtilis, Steven Grigsby
Undergraduate Theses—Unrestricted
The bacterial tubulin homologue FtsZ polymerizes in vitro in a GTP-dependent manner to form long, single stranded filaments. In cells, these filaments assemble at the nascent division site, interacting laterally to form the contractile Z ring. The Z ring serves as a scaffold for the rest of the division machinery and constricts at the leading edge of the invaginating septum during cytokinesis. The FtsZ polypeptide consists of three primary domains: the N-terminal globular core consisting of 315 residues that contains the GTP binding site, a variable and flexible C-terminal linker (CTL) consisting of 50 residues, and a conserved region at …
Transduction As The Method Of Horizontal Gene Transfer Of The Staphylococcal Chromosomal Cassette Mec (Sccmec),
2015
James Madison University
Transduction As The Method Of Horizontal Gene Transfer Of The Staphylococcal Chromosomal Cassette Mec (Sccmec), Amber B. Sauder
Senior Honors Projects, 2010-2019
Methicillin-resistant Staphylococcus aureus (MRSA) gains resistance to β-lactam antibiotics through a mutated penicillin binding protein (PBP2a) encoded on the SCCmec element. In combination with the recombinase encoded by ccr, these two genes are used as markers of the mobile genetic element (SCCmec). Due to recent increases in community acquired MRSA infections, the mechanisms of antibiotic resistance gene transfer have gained attention. Transduction, a method of horizontal gene transfer mediated by bacteriophage, is believed to be responsible for the movement of the SCCmec element. Recent studies have shown the transduction of the SCCmec element in clinical isolates; however, this study is …
Comparative Analysis Of Anti-Bd Bacteria From Six Malagasy Frog Species Of Ranomafana National Park,
2015
James Madison University
Comparative Analysis Of Anti-Bd Bacteria From Six Malagasy Frog Species Of Ranomafana National Park, Kelsey Savage
Senior Honors Projects, 2010-2019
As Malagasy amphibians are facing an impending extinction crisis from the lethal skin fungus Batrachochytrium dendrobatidis (Bd), it has become imperative to proactively mitigate the threat. Bd sporangia develop in the skin of infected amphibians and cause the skin to thicken, leading to ionic imbalance and eventual heart failure. It has been shown that certain bacterial species are able to inhibit Bd growth on amphibians by producing antifungal metabolites. Community-based probiotics are one approach used to combat chytridomycosis by inoculating an environment with Bd-inhibitory bacteria so that many amphibian species are treated at once. With this method, it is important …
Tonb Not Directly Related To Efflux Of Antibiotics In E. Coli,
2015
Bowling Green State University
Tonb Not Directly Related To Efflux Of Antibiotics In E. Coli, Amber Gombash
Honors Projects
Studies in Pseudomonas aeruginosa have suggested that the TonB energy transduction system directly contributes to efflux-mediated antibiotic resistance, ostensibly by energizing one or more efflux systems. We have found ∆tonB strains of Escherichia coli to similarly be more sensitive to certain antibiotics relative to wild-type strains. To test the hypothesis that this enhanced sensitivity involved the energization of efflux systems, sensitivity patterns for a variety of antibiotics were evaluated using a set of strains differentially lacking genes encoding the Acr efflux system, the universal outer membrane efflux portal TolC, and TonB. No correlation was evident between the resistance phenotypes of …
Combating Infectious Diseases In Aquaculture With An Original Probiotic Product,
2015
University of Rhode Island
Combating Infectious Diseases In Aquaculture With An Original Probiotic Product, Meagan Hamblin, Saebom Sohn, Christine Ahn Dao, Marta Gomez-Chiarri, David R. Nelson, David Worthen, David Rowley
Senior Honors Projects
Oyster production in Rhode Island accounts for over $2.5 million in annual revenue, making it the top aquaculture product in the state. However, larval tank infections significantly constrain production and create substantial economic losses for commercial hatcheries. In most cases antibiotics may not be used to prevent or treat larval tank infections. A probiotic, or beneficial microbe which competes with pathogens, is a safer and “green” approach to preventing infections. Vibriosis, a common cause of oyster larval mortality, is the result of Vibrio species infections. Previous studies have shown that a native Rhode Island microbe, Bacillus pumilus RI06-95, protects oyster …
Influence Of The Anti-Hiv Drug Elvitegravir On Chlamydial Development And The Characterization Of Chlamydial Polymorphic Membrane Protein Expression In Herpes Simplex Virus (Hsv)/C. Trachomatis Co-Infected Cells,
2015
East Tennessee State University
Influence Of The Anti-Hiv Drug Elvitegravir On Chlamydial Development And The Characterization Of Chlamydial Polymorphic Membrane Protein Expression In Herpes Simplex Virus (Hsv)/C. Trachomatis Co-Infected Cells, Hena Yakoob
Undergraduate Honors Theses
Chlamydia trachomatis is the most common bacterial agent of sexually transmitted infections worldwide and a common co-infection in AIDS patients. Chlamydial genital tract infections are often asymptomatic; therefore many infections go untreated and result in complications like chronic inflammation, ectopic pregnancy, and pelvic inflammatory disease. Chlamydia share a unique developmental cycle and under stress, can enter a state known as persistence, in which the bacteria are noninfectious but still viable. Removal of the stressor allows the chlamydiae to re-enter and complete the developmental cycle. Exposure to low-dose quinolones can cause the chlamydiae to enter persistence and halt the developmental cycle. …
Characterization Of Putative Exbb And Exbd Leads To The Identification Of A Potential Tol-Pal System In Rhizobium Leguminosarum Atcc 14479,
2015
East Tennessee State University
Characterization Of Putative Exbb And Exbd Leads To The Identification Of A Potential Tol-Pal System In Rhizobium Leguminosarum Atcc 14479, Valeria Barisic
Electronic Theses and Dissertations
Rhizobium leguminosarum is a Gram negative nitrogen-fixing soil bacterium. Due to the limited bioavailability of iron, bacteria utilize siderophores that scavenge and bind available iron. The transport of iron-siderophore complexes is achieved by the TonB-ExbB-ExbD complex. We have previously shown that a functional TonB protein is necessary for iron transport by creating ΔtonB mutants and assessing their growth and 55Fe-siderophore transport ability. We attempted to identify and characterize the roles of putative exbB and exbD genes using a similar approach. Growth curves and sequence analyses suggest putative exbB and exbD may be the tolpal-associated genes tolQ and tolR. Phenotypic and …
Functional Screening Of The Cronobacter Sakazakii Baa-894 Genome Reveals A Role For Prop (Esa_02131) In Carnitine Uptake,
2015
Department of Biological Sciences; Cork Institute of Technology; Cork, Ireland.
Functional Screening Of The Cronobacter Sakazakii Baa-894 Genome Reveals A Role For Prop (Esa_02131) In Carnitine Uptake, Audrey Feeney, Roy D. Sleator
Department of Biological Sciences Publications
Cronobacter sakazakii is a neonatal pathogen responsible for up to 80% of fatalities in infected infants. Low birth weight infants and neonates infected with C. sakazakii suffer necrotizing enterocolitis, bacteraemia and meningitis. The mode of transmission most often associated with infection is powdered infant formula (PIF) which, with an aw of ∼0.2, is too low to allow most microorganisms to persist. Survival of C. sakazakii in environments subject to extreme hyperosmotic stress has previously been attributed to the uptake of compatible solutes including proline and betaine. Herein, we report the construction and screening of a C. sakazakii genome bank and …
Potential For Biocontrol Of Environmental Vibrio Spp. By Predatory Bacteria Bacteriovorax,
2015
Old Dominion University
Potential For Biocontrol Of Environmental Vibrio Spp. By Predatory Bacteria Bacteriovorax, Patrick Tennis
OES Theses and Dissertations
The scale of predator-prey interactions varies from the iconic (e.g., lions and gazelles) to the microscopic (e.g., protists and bacteria). Bdellovibrio-and-like-organisms (BALOs) are bacteria that prey upon other Gram-negative bacteria, including pathogens. In particular, the halophilic genus Vibrio, many species of which are disease agents, has been shown to be susceptible to attack by BALOs. One motivation of the present research is to assess the potential for biocontrol of Vibrio by Bacteriovorax. This investigation is the first to test the susceptibility of Vibrio strains (n = 26) originating from a variety of geographic locations to predation by …
