Life Sciences Commons^™

Donor Platelet Plasma Components Inactivate Sensitive And Multidrug Resistant Acinetobacter Baumannii Isolates, Chelsea M. Edelblute, Olga N. Pakhomova, Fanying Li, Barbara Y. Hargrave, Loree C. Heller

Bioelectrics Publications

Acinetobacter baumannii is an environmentally resilient healthcare-associated opportunistic pathogen responsible for infections at many body sites. In the last 10 years, clinical strains resistant to many or all commonly used antibiotics have emerged globally. With few antimicrobial agents in the pharmaceutical pipeline, new and alternative agents are essential. Platelets secrete a large number of proteins, including proteins with antimicrobial activity. In a previous study, we demonstrated that donor platelet supernatants and plasma significantly inhibited the growth of a reference strain of A. baumannii in broth and on skin. This inhibition appeared to be unrelated to the platelet activation state. In …

Determining The Prevalence And Distribution Of Tick-Borne Pathogens In Southeastern Virginia And Exploring The Transmission Dynamics Of Rickettsia Parkeri In Amblyomma Maculatum, Chelsea L. Wright Thompson

Biological Sciences Theses & Dissertations

Tick-borne pathogens are an increasing threat to human and animal health worldwide. In the United States, cases of Lyme disease, spotted fever rickettsioses, ehrlichiosis and anaplasmosis are on the rise. Factors related to emergence include appearance of a new pathogen, recognition of an existing pathogen and environmental changes that result in new exposure events. Despite the rise in tick-borne disease incidence within many states, including Virginia, there is a paucity of data related to the prevalence and distribution of ticks and tick-borne pathogens.

The first aim of this dissertation research was to determine the tick-borne pathogen composition within tick populations …

Isquest: Finding Insertion Sequences In Prokaryotic Sequence Fragment Data, Abhishek Biswas, David T. Gauthier, Desh Ranjan, Mohammad Zubair

Computer Science Faculty Publications

Motivation: Insertion sequences (ISs) are transposable elements present in most bacterial and archaeal genomes that play an important role in genomic evolution. The increasing availability of sequenced prokaryotic genomes offers the opportunity to study ISs comprehensively, but development of efficient and accurate tools is required for discovery and annotation. Additionally, prokaryotic genomes are frequently deposited as incomplete, or draft stage because of the substantial cost and effort required to finish genome assembly projects. Development of methods to identify IS directly from raw sequence reads or draft genomes are therefore desirable. Software tools such as Optimized Annotation System for Insertion Sequences …

Section Abstracts: Biology With Microbiology And Molecular Biology

Virginia Journal of Science

Abstracts of the Biology with Microbiology and Molecular Biology Section for the 93rd Annual Meeting of the Virginia Academy of Science, May 21-23, 2015, James Madison University, Richmond, Virginia

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 …

Identification And Comparative Analysis Of Subolesin/Akirin Ortholog From Ornithodoros Turicata Ticks, Hameeda Sultana, Unnati Patel, Daniel E. Sonenshine, Girish Neelakanta

Biological Sciences Faculty Publications

Background: Subolesin is an evolutionary conserved molecule in diverse arthropod species that play an important role in the regulation of genes involved in immune responses, blood digestion, reproduction and development. In this study, we have identified a subolesin ortholog from soft ticks Ornithodoros turicata, the vector of the relapsing fever spirochete in the United States.

Methods: Uninfected fed or unfed O. turicata ticks were used throughout this study. The subolesin mRNA was amplified by reverse transcription polymerase chain reaction (RT-PCR) and sequenced. Quantitative-real time PCR (QRT-PCR) was performed to evaluate subolesin mRNA levels at different O. turicata developmental stages …

Subsistence Strategies In Traditional Societies Distinguish Gut Microbiomes, Alexandra J. Obregon-Tito, Raul T. Tito, Jessica Metcalf, Krithvivasa Sankaranarayanan, Jose C. Clemente, Luke K. Ursell, Zhenjiang Zech Xu, Will Van Treuren, Rob Knight, Morris Foster

Office of Research Faculty & Staff Publications

Recent studies suggest that gut microbiomes of urban-industrialized societies are different from those of traditional peoples. Here we examine the relationship between lifeways and gut microbiota through taxonomic and functional potential characterization of faecal samples from hunter-gatherer and traditional agriculturalist communities in Peru and an urban-industrialized community from the US. We find that in addition to taxonomic and metabolic differences between urban and traditional lifestyles, hunter-gatherers form a distinct sub-group among traditional peoples. As observed in previous studies, we find that Treponema are characteristic of traditional gut microbiomes. Moreover, through genome reconstruction (2.2-2.5 MB, coverage depth x26-513) and functional potential …

Iron Deficiency Increases Growth And Nitrogen-Fixation Rates Of Phosphorus-Deficient Marine Cyanobacteria, Nathan S. Garcia, Feixue Fu, Peter N. Sedwick, David A. Hutchins

OES Faculty Publications

Marine dinitrogen (N²)-fixing cyanobacteria have large impacts on global biogeochemistry as they fix carbon dioxide (CO₂) and fertilize oligotrophic ocean waters with new nitrogen. Iron (Fe) and phosphorus (P) are the two most important limiting nutrients for marine biological N₂ fixation, and their availabilities vary between major ocean basins and regions. A long-standing question concerns the ability of two globally dominant N₂-fixing cyanobacteria, unicellular Crocosphaera and filamentous Trichodesmium, to maintain relatively high N₂-fixation rates in these regimes where both Fe and P are typically scarce. We show that under P-deficient …

Heterotrophic And Autotrophic Contribution To Dinitrogen Fixation In The Gulf Of Aqaba, Eyal Rahav, Barak Herut, Margaret R. Mulholland, Natalia Belkin, Hila Elifantz, Ilana Berman-Frank

OES Faculty Publications

We evaluated the seasonal contribution of heterotrophic and autotrophic diazotrophy to the total dinitrogen (N₂) fixation in the photic zone of a pelagic station in the northern Gulf of Aqaba, Red Sea. N₂ fixation rates were highest during a Trichodesmium bloom in winter (0.7 nmol N l^-1 d^-1), decreased 7-fold 1 wk later throughout the upper 200 m (~0.1 nmol N l^-1) d^-1), and were significantly coupled with both primary and bacterial productivity. N₂ fixation rates were generally higher in the upper 200 m (~0.4 nmol N l^{-1 …}