Microbiology Commons^™

Does Triclosan Exposure And Tolerance Lead To Chlorine Resistant Bacteria?, Sherry Blackmon

Undergraduate Review

Triclosan is an antimicrobial agent added to a wide variety of medical and consumer care products such as soaps, deodorants, toothpastes, and cleaning supplies. Bacterial exposure to triclosan could lead to chlorine resistant bacteria. These bacteria may survive chlorination, the standard method used to disinfect our drinking water. Water samples were obtained downstream a wastewater treatment plant (WWTP) in Bridgewater, MA and reference virgin stream (VS) in Monroe, MA. Bacteria were isolated from water samples, exposed to triclosan (0.001 or 0.05mg/mL), and then exposed to chlorine (0.05g/mL). 49% of all bacterial strains increased chlorine resistance after at least one triclosan …

Identification Of The Role Of The Sal Locus In Streptococcus Pyogenes Virulence During Host-Pathogen Interactions, Phanramphoei Namprachan-Frantz

Wayne State University Dissertations

The pathogenesis of Streptococcus pyogenes is due to its ability to overcome and adapt to the harsh environment created by the host immune response. The focus of this project was the SalKR two-component regulatory system, which facilitates bacterial adaptation by responding to environmental signals during host pathogen-interactions. The first goal of this project was to determine a role in virulence for the SalKR regulatory system. The complete deletion of the salKR genes in the wild type S. pyogenes strain HSC5 produced a highly attenuated mutant in a Zebrafish infection model. The ΔsalKR mutant appeared to lose the ability to survive …

Disorder Predictors Also Predict Backbone Dynamics For A Family Of Disordered Proteins, Gary W. Daughdrill, Wade M. Borcherds, Hongwei Wu

Molecular Biosciences Faculty Publications

Several algorithms have been developed that use amino acid sequences to predict whether or not a protein or a region of a protein is disordered. These algorithms make accurate predictions for disordered regions that are 30 amino acids or longer, but it is unclear whether the predictions can be directly related to the backbone dynamics of individual amino acid residues. The nuclear Overhauser effect between the amide nitrogen and hydrogen (NHNOE) provides an unambiguous measure of backbone dynamics at single residue resolution and is an excellent tool for characterizing the dynamic behavior of disordered proteins. In this report, we show …

Evolutionary Variation Of Papillomavirus E2 Protein And E2 Binding Sites, Adam Rogers, Mackenzie Waltke, Peter C. Angeletti

Nebraska Center for Virology: Faculty Publications

Background: In an effort to identify the evolutionary changes relevant to E2 function, within and between papillomavirus genera, we evaluated the E2 binding sites (E2BS)s inside the long-control-region (LCR), and throughout the genomes. We identified E2BSs in the six largest genera of papillomaviruses: Alpha, Beta, Gamma, Delta, Lambda, and Xi-papillomaviruses (128 genomes), by comparing the sequences with a model consensus we created from known functional E2BSs (HPV16, HPV18, BPV1). We analyzed the sequence conservation and nucleotide content of the 4-nucleotide spacer within E2BSs. We determined that there is a statistically significant difference in GC content of the four-nucleotide E2BS …

Critical Role Of Leucine-Valine Change In Distinct Low Ph Requirements For Membrane Fusion Between Two Related Retrovirus Envelopes, Marceline Côté, Yi-Min Zheng, Kun Li, Shi-Hua Xiang, Lorraine M. Albritton, Shan-Lu Liu

Nebraska Center for Virology: Faculty Publications

Many viruses use a pH-dependent pathway for fusion with host cell membrane, the mechanism of which is still poorly understood. Here we report that a subtle leucine (Leu)-valine (Val) change at position 501 in the envelope glycoproteins (Envs) of two related retroviruses, jaagsiekte sheep retro-virus (JSRV) and enzootic nasal tumor virus (ENTV), is responsible for their distinct low pH requirements for membrane fusion and infection. The Leu and Val residues are predicted to reside within the C-terminal heptad repeat (HR2) region of JSRV and ENTV Envs, particularly proximal to the hairpin turn of the putative six-helix bundle (6HB). Substitution of …

Hiv-1 Effects On Neuropsychological Performance In A Resource-Limited Country, Zambia, Gabriel Holguin, Mwanza Banda, Elizabeth J. Willen, Costantine Malama, Kaseya O. Chiyenu, Victor C. Mudenda, Charles Wood

Nebraska Center for Virology: Faculty Publications

Zambia has substantially been affected by the HIV/AIDS epidemic with prevalence rates at 14% in a population estimated at 12 million. Yet, the extent of HIV-associated neurocognitive disorders (HAND) in this population remains to be clearly understood. A series of culturally appropriate neuropsychological (NP) assessments [International HIV Dementia Scale (IHDS), Color Trails Test 1 and 2, Grooved pegboard Test, and Time Gait Test] were used to test the effects of HIV on NP performance of HIV seropositive and seronegative individuals. Twenty-two percent HIV positive individuals ARV naïve met the criteria for IHDS-defined NP impairment. Gender significantly influenced the performance on …

Characterization Of Species C Human Adenovirus Serotype 6 (Ad6), Eric A. Weaver, Reeti Khare, Mathew L. Hillestad, Donna Palmer, Philip Ng, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

Adenovirus serotype (Ad5) is the most studied Ad. Ad1, 2, and 6 are also members of species C Ad and are presumed to have biologies similar to Ad5. In this work, we have compared the ability of Ad1, 2, 5, and 6 to infect liver and muscle after intravenous and intramuscular injection. We found that Ad6 was surprisingly the most potent at liver gene delivery and that Ad1 and Ad2 were markedly weaker than Ad5 and 6. To understand these differences, we sequenced the Ad6 genome. This revealed that the Ad6 fiber protein is surprisingly three shaft repeats shorter than …

Generation Of A Kupffer Cell-Evading Adenovirus For Systemic And Liver-Directed Gene Transfer, Reeti Khare, Shannon M. May, Francesco Vetrini, Eric A. Weaver, Donna Palmer, Amanda Rosewell, Nathan Grove, Philip Ng, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

As much as 90% of an intravenously (i.v.) injected dose of adenovirus serotype 5 (Ad5) is absorbed and destroyed by liver Kupffer cells. Viruses that escape these cells can then transduce hepatocytes after binding factor X (FX). Given that interactions with FX and Kupffer cells are thought to occur on the Ad5 hexon protein, we replaced its exposed hypervariable regions (HVR) with those from Ad6. When tested in vivo in BALB/c mice and in hamsters, the Ad5/6 chimera mediated >10 times higher transduction in the liver. This effect was not due to changes in FX binding. Rather, Ad5/6 appeared to …

Estimating The Impact Of Human Papillomavirus (Hpv) Vaccination On Hpv Prevalence And Cervical Cancer Incidence In Mali, Leree Tracy, Holly Gaff, Colleen Burgess, Samba Sow, Patti E. Gravitt, J. Kathleen Tracy

Biological Sciences Faculty Publications

Human papillomavirus vaccines have potential to reduce cervical cancer incidence and mortality; however, cultural and economic barriers may hinder success in developing countries. We assessed impact of a single vaccine campaign in Mali with use of mathematical modeling. Our model shows that decreases in the prevalence of Human papillomavirus infection are proportional to achieved vaccination coverage.

Potential Fossil Endoliths In Vesicular Pillow Basalt, Coral Patch Seamount, Eastern North Atlantic Ocean, Barbara Cavalazzi, Frances Westall, Sherry L. Cady, Roberto Barbieri, Frédéric Foucher

Geology Faculty Publications and Presentations

The chilled rinds of pillow basalt from the Ampere-Coral Patch Seamounts in the eastern North Atlantic were studied as a potential habitat of microbial life. A variety of putative biogenic structures, which include filamentous and spherical microfossil-like structures, were detected in K-phillipsite-filled amygdules within the chilled rinds. The filamentous structures (similar to 2.5 mu m in diameter) occur as K-phillipsite tubules surrounded by an Fe-oxyhydroxide (lepidocrocite) rich membranous structure, whereas the spherical structures (from 4 to 2 mu m in diameter) are associated with Ti oxide (anatase) and carbonaceous matter. Several lines of evidence indicate that the microfossil-like structures in …

Purification, Characterisation And Applications Of A Cloned Staphylococcal Bacteriophage Lysin For The Control Of Multi-Drug Resistant Staphylococcus Aureus Including Mrsa, Mark Fenton

Theses

The work presented in this thesis focuses on the purification, characterisation and practical applications of an anti-staphylococcal lysin (LysK) and its single-domain truncated derivative (CHAP_k) against pathogenic staphylococci including meticillin resistant Staphylococcus aureus (MRSA). Both proteins were purified to greater than 90% homogeneity. Affinity chromatography was applied as the optimum method for LysK purification and ion-exchange chromatography was successfully applied to CHAP_k. The lytic spectrum of LysK was investigated by zymogram analysis where the enzyme exhibited strong activity against a range of staphylococci regardless of their origin, sequence type (ST) or antibiotic resistant profile. This analysis …

The Evolution Of Bacteriophages E11/2 And E4/Lc For Control Of Verocytotxigenic E.Coli At Key Stages In The Beef Chain, Bríd Coffey

Theses

The objective of this thesis was lo evaluate the potential of bactcriophages e4/1 c and cl 1/2 ns biocontrol agents for E. coli O157:H7. Initially, e4/lc and el 1/2 were subjected to high-throughput 454 sequencing. The data generated revealed that e4/I c (47,112 bp) is very similar to the lytic E. coli phages RTP and JK06. Interestingly, differences within the tail module led to the identification of a putative site of attachment to E. coli O157:H?. Comparative genomic analysis indicated that el 1/2 (168,470 bp) is a novel member of the T-even group, with high degrees of similarity to T4 …

Biosolar Conversion Of N2 And H2o To Ammonia By Engineered N2-Fixing Cyanobacteria, Seth T. Harris

The Journal of Undergraduate Research

The cyanobacterium Anabaena sp. PCC 7120 is capable of using solar energy to produce ammonia through conversion of atmospheric dinitrogen in differentiated cells called heterocysts. Harnessing this system could enable cyanobacteria to be used in ammoniafertilizer production, creating a renewable alternative to the current Haber-Bosch process. The genes patA and alr3304 in the Anabaena 7120 genome are important in heterocyst formation; an increase in heterocyst formation is seen with over-expression of patA or inactivation of alr3304. This research aims to create a novel mutant that forms more heterocysts by simultaneously over-expressing patA and inactivating alr3304, producing higher amounts of ammonia. …

Laser-Induced Breakdown Spectroscopy (Libs): An Innovative Tool For Studying Bacteria, Qassem I. Mohaidat

Wayne State University Dissertations

Laser-induced breakdown spectroscopy (LIBS) has gained a reputation as a flexible and convenient technique for rapidly determining the elemental composition of samples with minimal or no sample preparation. In this dissertation, I will describe the benefits of using LIBS for the rapid discrimination and identification of bacteria (both pathogenic and non-pathogenic) based on the relative concentration of trace inorganic elements such as Mg, P, Ca, and Na. The speed, portability, and robustness of the technique suggest that LIBS may be applicable as a rapid point-of-care medical diagnostic technology.

LIBS spectra of multiple genera of bacteria such as Escherichia, Streptococcus, Mycobacterium, …

Evaluation Of A Biopesticide Against Invasive Species For Native Species Restoration, Denise Ann Mayer

Legacy Theses & Dissertations (2009 - 2024)

Since their introduction in the 1980s, dreissenid mussels (Dreissena polymorpha and D. rostriformis bugensis) rapidly spread throughout North America and have had severe impacts on the ecology of freshwater ecosystems. A project was initiated in the early 1990s at the New York State Museum's Field Research Laboratory to discover and develop natural products to control industrial biofouling by dreissenid mussels. A strain of Pseudomonas fluorescens (Pf-CL145A), isolated from the sediment of a North American river, was found to be effective at killing dreissenids. The strain was patented for this use.

Herpes Simplex Virus Type 1 : Interactions With The Cellular Proteasome And Microrna Pathways, Daniel Joseph Munson

Legacy Theses & Dissertations (2009 - 2024)

Herpes Simplex Virus Type 1 (HSV-1) is a human pathogen that is estimated to have infected 60-80% of the population worldwide, causing oral lesions, encephalitis, and blindness. Infection results in life-long latency of the virus, with periods of reactivation and symptomatic disease. Early in infection, HSV-1 induces the formation of replication compartments and VICE (virus induced chaperone enriched) domains within the nucleus. Adjacent to VICE domains, we observed foci which contained Mss1, a cellular protein normally associated with the proteasome. Mss1 belongs to the AAA-ATPase family of proteins, which have been shown to function in DNA repair, transcription, translation, and …

Banf1 Is Required To Maintain The Self-Renewal Of Both Mouse And Human Embryonic Stem Cells, Jesse L. Cox, Sunil K. Mallanna, Briana D. Ormsbee, Michelle Desler, Matthew S. Wiebe, Angie Rizzino

Nebraska Center for Virology: Faculty Publications

Self-renewal is a complex biological process necessary for maintaining the pluripotency of embryonic stem cells (ESCs). Recent studies have used global proteomic techniques to identify proteins that associate with the master regulators Oct4, Nanog, and Sox2 in ESCs or in ESCs during the early stages of differentiation. Through an unbiased proteomic screen, Banf1 was identified as a Sox2- associated protein. Banf1 has been shown to be essential for worm and fly development but, until now, its role in mammalian development and ESCs has not been explored. In this study, we examined the effect of knocking down Banf1 on ESCs. We …

Analysis Of The Streptococcal Cpsa Protein In Dna-Binding And Regulation Of Capsule And Cell Wall Maintenance, Brett R. Hanson

Wayne State University Dissertations

The systemic pathogens Streptococcus agalactiae (GBS) and Streptococcus pneumoniae remain a significant threat to human health worldwide. The ability of these organisms to cause systemic disease is compounded by the production of a polysaccharide capsule that provides immune evasion function. The production of the polysaccharide capsule in systemic streptococcal pathogens is controlled in part by the membrane bound protein CpsA. These studies analyze the contribution of CpsA to regulation of capsule level in the model aquatic pathogen Streptococcus iniae and human specific pathogen GBS, and how this regulation affects virulence in in-vitro, ex-vivo, and in-vivo models of pathogenesis. We have …

Efficacy Of The Pentavalent Rotavirus Vaccine, Rotateq (Rv5), Between Doses Of A 3-Dose Series And With Less Than 3 Doses (Incomplete Regimen), Penelope D. Dennehy, Timo Vesikari, David O. Matson, Robbin F. Itzler, Michael J. Dallas, Michelle G. Goveia, Mark J. Dinubile, Penny M. Heaton, Max Ciarlet

Community & Environmental Health Faculty Publications

Post-hoc analyses of the Rotavirus Efficacy and Safety Trial (RES T) were conducted to determine whether the pentavalent rotavirus vaccine (RV5) confers early protection against rotavirus gastroenteritis (RVGE) before completion of the 3-dose regimen. To evaluate the efficacy of RV5 between doses in reducing the rates of RVGE-related hospitalizations and emergency department (ED) visits in infants who ultimately received all 3 doses of RV5/placebo, events occurring from 2 weeks after the first and second doses to receipt of the subsequent dose (Analysis A) and events occurring from 2 weeks after the first and second doses to 2 weeks after the …

Surface Entropy Reduction To Increase The Crystallizability Of The Fab-Rna Complex, Priyadarshini Palaniandy Ravindran

Electronic Theses and Dissertations

Crystallizing RNA has been an imperative facet and a challenging task in the world of RNA research. Assistive methods such as Chaperone Assisted RNA Crystallography (CARC), employing monoclonal antibody fragments (Fabs) as crystallization chaperones have enabled us to obtain RNA crystal structures by increasing the crystal contacts and providing initial phasing information. Using this technology the crystal structure of [delta]C209 P4-P6 RNA (an independent folding domain of the self-splicing Tetrahymena group I intron) complexed to Fab2 (high affinity binding Fab) has been resolved to 1.95 Å (1). Although the complexed class I ligase ribozyme has also been crystallized using CARC …