Environmental Microbiology and Microbial Ecology Commons^™

Microbial Guardians Of The Savannah: Unraveling The Gut Microbiome For African Carnivore Conservation, Laura E. Peirson

All NMU Master's Theses

Non-invasive fecal sampling is essential for wildlife gut microbiome (GMB) research, yet field conditions often limit preservation options. I compared gut bacterial communities in paired fecal samples preserved in stabilization tubes and air-dried in paper bags collected from anesthetized African lions (Panthera leo) and spotted hyenas (Crocuta crocuta) in Etosha National Park, Namibia. Additional opportunistic samples from carnivore kill sites were also analyzed. No significant differences in alpha or beta diversity were detected between preserved and dried samples, although bacterial beta diversity differed between preserved and opportunistic samples (PERMANOVA). Core bacterial communities remained consistent across sample …

Archaeal Diversity In The Anna's Hummingbird Microbiome, Lauren E. Chance

Honors Scholar Theses

The microbial communities that are present in and on vertebrates are collectively called the microbiome. The composition of a microbiome is dependent upon the host, the environment, and evolution. There has been extensive research on the bacterial composition of host-associated microbiomes, however, there has been much less work on the archaeal composition of host-associated microbiomes. Archaea have previously been assumed to primarily exist in extreme environments, but this may not be true and has been influenced by their generally low abundance and methodological difficulties in detection. It is possible they are consistent members of diverse host-associated microbiomes.

Archaea-specific PCR primers …

Using Single Cell Genomics To Explore The Impact Of Marine Viruses On Microbial Respiration., Paxton Tomko

MCB Articles

Viral metabolic reprograming of marine prokaryotes, through the use of virally encoded auxiliary metabolic genes (AMGs), plays a critical role in marine ecosystem function by influencing biochemical cycles and genetic diversity in these environments. Despite the fundamental role viruses play in global environmental ecosystems, they remain an understudied aspect of microbial ecology and evolution, in part due to the methods available for studying virus host interactions in natural systems. Thus far, metagenomic analyses have been used to study the interactions of virus host pairs, but these types of analyses have their limitations in accurately linking viruses to hosts, or culture-based …

Identification Of Novel Biosynthetic Gene Clusters Encoding For Polyketide/Nrps-Producing Chemotherapeutic Compounds From Marine-Derived Streptomyces Hygroscopicus From A Marine Sanctuary, Hannah Ruth Flaherty

Honors Theses and Capstones

Nearly one out of six deaths in 2020, around ten million people, were caused by cancer, making it a leading cause of death worldwide (WHO, 2022). This major public health issue, in addition to the rise of multidrug-resistant (MDR) pathogens, provides a high demand for the discovery of new pharmaceutical drugs to be used clinically to treat these conditions. The Streptomyces genus accounts to produce 39% of all microbial metabolites currently approved for human health, indicating its potential as an important species to study for antimicrobial and anticancer agents. The long linear genome of Streptomyces contains specialized sequences known as …

The Expanding Marine Built Environment And Biofilm Formation Processes, Rachel Mugge

Dissertations

The marine built environment (i.e., places or things made or modified by humans) in the northern Gulf of Mexico is rapidly expanding and includes over 2,000 known historic shipwrecks, nearly 4,100 artificial reefs, and other built structures for natural resource extraction, marine aquaculture, renewable energy generation, munitions dumping areas, and commercial and recreational activities. While these structures have the potential to develop into artificial reefs, acting as biodiversity hotspots that provide food and shelter and facilitate organism transport, it is unclear how they affect biodiversity and ecosystem function in the marine environment. The success of artificial reefs to become ecosystems …

Alterations Of The Gut Mycobiome In Patients With Ms - A Bioinformatic Approach, Saumya Shah

Honors Scholar Theses

The mycobiome is the fungal component of the gut microbiome and is implicated in several autoimmune diseases. However, its role in multiple sclerosis (MS) has not been studied. We performed descriptive and formal statistical tests using the R language to characterize the gut mycobiome in people with MS (pwMS) and healthy controls. We found that the microbiome composition of multiple sclerosis patients is different from healthy people. The mycobiome had significantly higher alpha diversity and inter-subject variation in pwMS than controls. Additionally, Saccharomyces and Aspergillus were over-represented in pwMS. Different mycobiome profiles, defined as mycotypes, were associated with different bacterial …

A Comparative Taxonomic And Diversity Study Of Litter-Associated Fungi In Northwest Arkansas Forests, Rajaa Abdulrazzaq Abbas Al Aanbagi

Graduate Theses and Dissertations

Fungi are taxonomically the most species-rich group of organisms on the earth, ecologically occupy distinctive niches and interact with diverse other organisms throughout their biogeographic distributions and functionally play key roles through their various lifestyles. Plant litter, in particular, is a keystone component in ecosystems and provides heterogeneous microhabitats for the often overlooked litter-decomposing fungi and other organisms on the floor of temperate deciduous forests. Litter fungi involve indirect interactions with the plant, soil and whole food web network. However, the community structure and functions of litter-associated fungi as well as patterns of species richness distributed across various litter microhabitats …

Microbial Ecology Of South Florida Surface Waters: Examining The Potential For Anthropogenic Influences, Chase P. Donnelly

HCNSO Student Theses and Dissertations

South Florida contains one of the largest subtropical wetlands in the world, and yet not much is known about the microbes that live in these surface waters. These microbes play an important role in chemical cycling and maintaining good water quality for both human and ecosystem health. The hydrology of Florida’s surface waters is tightly regulated with the use of canal and levee systems run by the US Army Corps of Engineers and The South Florida Water Management District. These canals run through the Everglades, agriculture, and urban environments to control water levels in Lake Okeechobee, the Water Conservation Areas, …

A Cure For Salmonella: Engaging Students In Pathogen Microbiology And Bioinformatics, Sophie Jurgensen

Senior Honors Projects, 2010-2019

Advances in Next Generation Sequencing (NGS) technology have generated a vast amount of publicly available genomic data, creating a need for students with training in computational analysis. This laboratory lesson is a course-based undergraduate research experience (CURE) focusing on environmental Salmonella, a common foodborne pathogen that is of great interest to public health laboratories but is relatively less virulent than most other such pathogens. As discovery is a central tenet of CUREs, students isolate novel Salmonella enterica and related strains from stream sediment, poultry litter, or other sources in the first half of the lesson (Module 1). They also …

Fungi Of Forests: Examining The Diversity Of Root-Associated Fungi And Their Responses To Acid Deposition, Donald Jay Nelsen

Graduate Theses and Dissertations

Global importance of forests is difficult to overestimate, given their role in oxygen production, ecological roles in nutrient cycling and supporting numerous living species, and economic value for industry and as recreational zones. Fitness of the forest-forming trees strongly depends on microbial communities associated with tree roots. In particular, fungi impact tree fitness: mycorrhizal species provide water and nutrients for the trees in exchange for C, endophytic fungi play key roles in host defense against pathogenic organisms, and saprotrophic fungi decompose dead organic matter and facilitate nutrient cycling. In addition, pathogenic fungal species strongly affect forest fitness. Despite their importance, …

An Exploration Of The Phylogenetic Placement Of Recently Discovered Ultrasmall Archaeal Lineages, Jeffrey M. O'Brien

Honors Scholar Theses

In recent years, several new clades within the domain Achaea have been discovered. This is due in part to microbiological sampling of novel environments, and the increasing ability to detect and sequence uncultivable organisms through metagenomic analysis. These organisms share certain features, such as small cell size and streamlined genomes. Reduction in genome size can present difficulties to phylogenetic reconstruction programs. Since there is less genetic data to work with, these organisms often have missing genes in concatenated multiple sequence alignments. Evolutionary Biologists have not reached a consensus on the placement of these lineages in the archaeal evolutionary tree. There …