Life Sciences Commons^™

The Characterization Of The Type I Dna Methyltransferase Hsdm1 (Hp0463) In Helicobacter Pylori, Elise Zimmerman

Undergraduate Honors Theses

Helicobacter pylori is a gram-negative spiral-shaped bacterium that colonizes the gastric epithelium and is the leading cause of gastric adenocarcinoma globally. For both H. pylori and many other bacterial species, there is an increasing body of evidence that methylation by restriction-modification systems regulates gene expression in addition to its traditional role in genome protection. The study aimed to further elucidate the mechanisms through which H. pylori achieves methylome plasticity. We demonstrated that the Type I DNA methyltransferase hsdM1 (HP0463) is regulated by the main acid sensing mechanism of H. pylori, the two-component system (TCS) ArsRS. ArsRS induces hsdM1 …

Using A Machine Learning Model To Predict Plant Inflorescences Based Upon Its Soil Microbiome, Luke Denoncourt

Undergraduate Honors Theses

The UN estimates that the global population could reach 9.7 billion by 2050 (United Nations). As a result, the amount of food required to feed humanity is thought to double by 2050 (Ray et al., 2012). Humanity must find a way to increase crop production without increasing fertilizer usage and eutrophication, which can be done using the soil microbiome. Using potted plants with soils inoculated with Pseudomonas alcaligenes, Pseudomonas denitrificans, Bacillus polymyxa, and Mycobacterium phlei, both the shoot and root growth of pea and cotton plants was significantly increased (Egamberdieva & Höflich, 2004). In this study, utilizing a random forest …

Analysis Of Edna To Assess Effects Of Water Quality On Freshwater Fungal Diversity In A Virginia Coastal Watershed, Lauren French

Undergraduate Honors Theses

Freshwater fungi comprise a phylogenetically and functionally diverse group which contributes to wide-ranging ecosystem processes in aquatic systems. Saprotrophic fungi convert detritus into nutrient-rich food sources for fish and invertebrates, whereas pathogenic and parasitic fungi can cause disease and population declines of other aquatic organisms. With their diverse and important roles, changes in freshwater fungal community structure may have far-reaching impacts on ecosystems. To understand how natural and anthropogenic stressors to freshwater systems impact fungal-mediated ecosystem processes, a greater understanding of the taxonomic and functional composition of freshwater fungal communities is needed. We assessed relationships among freshwater habitat types, water …

Mysteries And Uncertainties In Tracing Cryptic Viral Infections, Melaina Jacoby

Undergraduate Honors Theses

Viruses are the most abundant biological entities on Earth. Viral impacts are evident from the level of individual cells and population all the way up to ecosystems and global elemental cycles. Since bacteriophages (viruses that infect bacteria) were first identified in the early twentieth century, the study of these fascinating entities has shown how viral dynamics within ecosystems can influence microbially-mediated processes at a large scale. Viral infections can impact hosts and host-mediated processes in in multiple ways, one of which is through cryptic infections. This state, in which a bacterium may harbor a cryptic phage infection, is known as …

Characterizing The Microbiome Of Floral Nectar Of Asclepias Syriaca And Other Asclepias Species, Heather Natterer

Undergraduate Honors Theses

In recent decades, Danaus plexippus (the monarch butterfly) has experienced a drastic decrease in population size due to urbanization, climate change, and habitat loss. The primary habitat and food source of D. plexippus is plant species that are within the genus Asclepias (milkweed). The preservation and propagation of Asclepias spp. is necessary to combat D. plexippus’s population declines. A plant’s reproductive success is dependent upon its ability to attract pollinators, which is linked to the plant’s nectar qualities. We propose that, in turn, these nectar qualities may be influenced by the nectar microbiome. This study aims to better understand the …

Proteomic Analysis Of Mycobacteriophage Crimd, William Moeller

Undergraduate Honors Theses

Bacteriophages represent a large portion of the biomatter on our planet, and many of them have yet to be fully characterized. Here we discuss the proteomic analysis of a particular Bacteriophage, Mycobacteriophage CrimD. This phage was discovered on the Campus of William & Mary and has had its genome characterized. We took the next logical step of proteomic analysis.

In our analyses we made use high pressure liquid chromatography paired with linear ion trap mass spectrometry to analyze the proteome of CrimD at specific time points after the infection of its host, Mycobacterium smegmatis. Additionally, we used nanospray ionization with …