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Characterization Of Bacterial Communities In Biscayne Bay Through Genomic Analysis, Eric Fortman

HCNSO Student Theses and Dissertations

Biscayne Bay is a shallow oligotrophic estuary in Southeast Florida. Channelization of rivers, and dredging of canals has greatly altered the historical flow of fresh water into the bay. This, coupled with the rise of a sprawling urban & suburban development, has greatly increased the nutrient load in the bay. This study examined the bacterial community at 14 stations throughout Biscayne Bay —6 stations were located at the mouths of canals; 1 upstream-canal station; 6 stations in the center of the bay; and one ocean influenced station, located near the entrance to the bay. One liter, surface water samples were …

Inferred Function And Dynamics Of Microbial Communities From The Northern Gulf Of Mexico, Deepesh Tourani

HCNSO Student Theses and Dissertations

Microbial communities, or microbiomes, are the major drivers of global biogeochemical cycles, acting as primary producers and decomposers across the water column in the oceans. Thus, they reflect changes in physicochemical properties and nutrient composition of the ocean. However, this correlation between ecological changes and the function of marine microbiomes is poorly understood. Large-scale oceanic events such as the bottom-water oxygen-depleted zone (i.e., “dead zone”) and the Deepwater Horizon oil spill in the Gulf of Mexico (GoM) render the ecosystem fragile. These events decrease survival rates of pelagic and coastal macrofauna and affect the biodiversity of the region. As part …

Changes In Soil Microbial Communities After Long-Term Warming Exposure, William G. Rodríguez-Reillo

Doctoral Dissertations

Microbial metabolism is a key controller of ecosystem processes (e.g., carbon cycling). However, we are only starting to identify the molecular mechanisms and feedback in response to long-term warming. My dissertation integrates multi-omics techniques to capture changes in soil microbial communities after long-term warming exposure. The research projects leverage three warming sites (i.e., SWaN, Barre Woods, and Prospect Hill) located in Western Massachusetts at Harvard Forest. These sites provided a unique experimental setup to better understand microbes in response to long-term temperature change. For the three research projects, we delved into the (i) microbial biodiversity across all three warming sites, …

Mechanisms Of Nestmate Recognition Cue Production In The European Honey Bee, Apis Mellifera., Cassondra Leigh Vernier

Arts & Sciences Electronic Theses and Dissertations

Social insects are some of the world’s most ecologically successful animal groups, and their complex societies are considered one of the pinnacles of animal evolution. Since these organisms live in colonies composed of many individuals and stored resources, they are a target for intruders, such as parasites, predators and conspecific robbers. Therefore, many social insect species have evolved mechanisms for nest defense, including nestmate recognition, where guarding individuals at the entrance of the colony use cues on incoming individuals to determine whether they are nestmates or intruders. Although nestmate recognition is incredibly important for maintaining colony integrity and fitness, the …

Secretory Iga Enhances Gut B Cells Priming And Systemic Igg Responses Towards Commensals, You Zhou

Arts & Sciences Electronic Theses and Dissertations

IgA is the primary antibody response at mucosal surfaces and is reported to inhibit adaptive immune responses against gut bacteria. Here, we utilize an in vitro system to expand and screen IgA memory B cells for their ability to recognize gut bacteria in the context of secretory IgA (sIgA) deficiency in polymeric Ig receptor (Pigr–/–) mice. Contrary to the prevailing hypothesis that IgA provides an immune exclusionary function, we found that mice lacking sIgA showed decreased anti-bacterial IgA specificities as assessed using flow cytometry. IgA B cell responses against certain taxa such as those of order Bacteriodales showed greater dependence …

The Endosymbiotic Gut Fungus Zancudomyces Culisetae Influences Transstadial Transmission Of Host-Associated Microbiota In The Yellow Fever Mosquito (Aedes Aegypti), Jonas Frankel-Bricker

Boise State University Theses and Dissertations

Mosquitoes are vectors for a variety of human pathogens and have a significant impact on human health worldwide. There is growing evidence that host-associated microbiota influence mosquito vector competence for certain viruses. Transstadial transmission of bacteria from larvae through pupae to adults could affect these interactions, though further studies are needed to fully unravel the mechanisms involved. Current microbiome research primarily focuses on bacterial communities, whereas the potential role endosymbiotic gut fungi have in transstadial transmission dynamics remains largely unknown. Trichomycetes is an ecological group of endosymbiotic microfungi that colonize the digestive tracts of arthropod hosts, including the Yellow Fever …

Regulation Of Immune Cell Activation And Functionby The Nbmpp2 Protein Andthe Cd5 Co-Receptor, Claudia Mercedes Freitas

Theses and Dissertations

According to the centers for disease control and prevention (CDC) and the world healthorganization (WHO), heart disease and immune related diseases such as diabetes and cancer areamong the leading causes of death around the world. Thus, the regulation of the function ofimmune cell plays a key role in health and disease. Calcium (Ca2+) ions play a critical role inimmune cell activation, function and in a robust immune response. Defects in Ca2+ signalinginfluences the development of cardiac disease, Alzheimer disease, immune cell metabolism,muscle dysfunction, and cancer. Each immune cell is unique in its activation and function,making it relevant to understand how …

Assessment Of Presumed Sterility Of The Human Placenta And Maternal Bladder, Ali Alhousseini

Wayne State University Dissertations

Introduction

Preterm birth is the number one cause of neonatal morbidity and mortality. A causal link has been established between infection and preterm birth. Urinary tract infection is the number one infection in pregnancy. Evaluating the existence of a placental and maternal bladder microbiome is a major scientific and clinical milestone in perinatal medicine.

Methodology and Results

Chapter 2: This is a prospective case control study. 69 placentas were collected in a sterile fashion from six groups of women without infection: Term cesarean not in labor (n=18), term cesarean in labor (n=9), term vaginal (n=21), preterm cesarean not in labor …

Alcohol Induced Bacterial Changes In The Setting Of Colitis, Paulius Kuprys

Dissertations

Inflammatory bowel diseases (IBD) affect a large number of individuals around the world. This group of diseases is largely composed of two types: Crohn's disease (CD) and ulcerative colitis (UC). Upon development of IBD, patients experience cyclical episodes of inflammation, known as flares. Flare induction appears to arise from multiple factors, which can also vary on a person-to-person basis. Alcohol has been shown to trigger IBD flares and onset, though the underlying mechanism has not been established.Defining factors of the IBD intestinal environment include an altered microbiome, bacterial infiltration of the intestinal epithelium, and increased leakage of proinflammatory bacterial byproducts. …

Longitudinal Urinary Microbiome Studies: A Need To Transition To Voided Urine, Baylie Hochstedler

Master's Theses

It is now established that the bladder is not sterile; it contains communities of microbes (microbiota). While the healthy bladder microbiota have been defined using expanded quantitative urine culture (EQUC) and urines obtained by transurethral catheterization (TUC), longitudinal and population studies have not previously been possible. These studies cannot be done using TUC urines, as it would be impractical to catheterize participants daily. Instead, we must transition to using voided urines.In order to make this switch, we have addressed three main issues raised by using voided urine. First, we showed that EQUC out performs standard urine culture on voided urines …

Shrimp Production Environment And The Gut Microbiome: Effects Of Aquaculture Practices And Selective Breeding On The Gut Microbiome Of Pacific Whiteleg Shrimp, Litopenaeus Vannamei, Angela Landsman

Electronic Theses and Dissertations

Knowledge of the functional role of the gut microbiome in animal health and nutrition may provide solutions to shrimp aquaculture challenges, such as improving disease resistance and optimizing growth particularly with low cost feeds. Successful manipulation of bacteria found in the gut requires a deeper understanding of shrimp microbial communities and how their compositional structure is influenced by environmental conditions, and inherent host factors such as genetics. The initial research investigated the intestinal bacterial communities of the Pacific whiteleg shrimp (Litopenaeus vannamei) reared in pond systems compared to indoor aquaculture facilities as an exploration of the effects of aquaculture practices …

Coaggregation Patterns And Surface Characteristics Of Lactobacillus Rhamnosus Gg Under Varying Nutrient Conditions, Amanda Rielinger

Senior Honors Theses and Projects

Lactobacillus rhamnosus GG (LGG) is one of the best studied probiotic organisms. The ability of probiotics to adhere to other microorganisms and the intestinal epithelium is thought to play a major role in their protective functions. Coaggregation is an important mechanism for biofilm formation by microorganisms. The goals of this study were to examine the ways in which nutrient variation affects intercellular interactions between LGG and other gut microbes and the hydrophobic character of LGG. We hypothesized that nutritional variation may affect the ability of LGG to coaggregate and form biofilms and thus affect its probiotic characteristics and ability to …

A Comparative Study Of Equine Gut Microbiomes Using 16s And 18s Rrna Sequencing, Jillian Jorgenson

Undergraduate Honors Thesis Projects

The gut microbiome of domestic horses (Equus ferus caballus) can be broken down into two primary divisions of interest: (1) prokaryotic composition, consisting of bacteria and archaea and (2) fungal composition. Within the gut, there are also eukaryotic parasite communities that may interact with the microbiome. While each has been the subject of various scientific explorations, in this study we analyze the potential interconnectedness of these categories. To determine the extent to which each component of the gut microbiome/parasitic communities influences the other, DNA was extracted and amplified from the fecal samples of eight horses. A combination of …

Environnmental Influences On Caribbean Octocoral-Symbiodiniaceae Symbioses, Mark Mccauley

Electronic Theses and Dissertations

A Caribbean octocoral colony is an assemblage of the octocoral host, dinoflagellate algae (family Symbiodiniaceae), bacteria and other microbes, together functioning as meta-organism (holobiont). Even though octocorals dominate many Caribbean reefs, compared to scleractinian corals, little is known about their biology under ambient or potentially stressful conditions. Of the nine species of octocorals (gorgonian corals, Order: Alcyonacea) studied, each had significantly different polyp behaviors, biochemical compositions, Symbiodiniaceae parameters, isotopic signatures, in addition to hosting distinct microbial assemblages. We identified multiple Symbiodiniaceae species (Breviolum minutum, Breviolum B41, Breviolum B1a and Breviolum B1i), inhabiting the gorgonians. These symbioses were temporally and …

Effects Of Weight Loss On Gut Microbiota, Samitinjaya Dhakal

Electronic Theses and Dissertations

Incidence of obesity continues to rise for several decades now. Despite the availability of the multiple weight loss programs, losing or maintaining weight remains a universal challenge. A comprehensive lifestyle modification is usually the cornerstone for achieving weight loss. A wealth of new information on gut microbial responses to diet to impact human health has introduced a new frontier in nutrition science that may help better understand inter-individual response variations to weight-loss interventions. This observational study examined the microbiota changes after weight-loss in relation to age, sex, and body-composition features in adults. A 10% reduction in body weight resulted in …