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Bacterial Diversity Of The Gut Of Cotinis Nitida, Roy Attila Kucuk

All Theses

Adult and larval Holometabolous insects exhibit radically different gut morphologies tied to their differing natural histories. Additionally, like other animals, these organisms frequently show distinctive morphological and physiological partitioning of their digestive systems, and this reflects on resident microbial communities. A review of the literature reveals bacteria have formed various symbioses with holometabolous hosts, differing widely in the context of host-symbiont services and patterns of colonization. The significance of these organisms in shaping host evolution and vice-versa is, at present, unclear, but intriguing in the context of host phylogeny.

Using high throughput 16S amplicon sequencing, the bacterial community of the …

Isolation Of Caldatribacterium (Op9) And Investigation Of Its Potential Interactions With A Novel, Co-Cultivated Thermodesulfobacterium Species, Toshio Alvarado

Electronic Theses, Projects, and Dissertations

Atribacteria (OP9), candidate phylum with no representatives in pure culture, is found in various anaerobic environments worldwide. “Caldatribacterium”, a lineage within Atribacteria that is predicted to be a strictly anaerobic sugar fermenter based on cultivation-independent genomic analyses, is currently being maintained in lab enrichment cultures with fucose as its sole growth substrate. Metagenomics and 16S rRNA gene tag sequencing indicated that the fucose culture was a co-culture of “Caldatribacterium” and an uncultivated member of the genus Thermodesulfobacterium. Due to failed attempts to isolate “Caldatribacterium” by dilution-to-extinction and plating, it was hypothesized that “Caldatribacterium” is dependent in some way on the …

Occurrence Of Aflatoxin And Zearalenone In Concentrate Feeds And Milk Contamination With Aflatoxin M1 And Bacterial Pathogens In Malawi, Chunala Alexico Njombwa

LSU Doctoral Dissertations

Multiple studies were conducted in Malawi to: 1) evaluate knowledge and perception of dairy farmers towards molds, mycotoxins and associated adverse effects; 2) evaluate dairy farmers’ knowledge and perception on milk contamination, proper milk handling practices and adverse health effects associated with raw milk consumption; 3) determine levels of aflatoxins and zearalenone (ZEN) in concentrate feedstuffs; 4) assess prevalence and levels of aflatoxin M₁(AFM₁) in raw milk, dietary exposure and estimate HCC risks to children and adults; 5) assess Salmonella and E. colicontamination in raw and processed milk from selected small scale farms and major …

Iron-Virus Interactions: Development And Testing Of The Ferrojan Horse Hypothesis, Chelsea Bonnain

USF Tampa Graduate Theses and Dissertations

Iron is an essential micronutrient for phytoplankton metabolism that limits growth in many regions of the surface ocean. More than 99.9% of oceanic dissolved iron is organically complexed to an iron-binding ligand, many of which have yet to be characterized. This thesis puts forth the Ferrojan Horse Hypothesis, which predicts a role for marine phages in oceanic iron cycling. Based on evidence from non-marine model systems, the Ferrojan Horse Hypothesis suggests that some marine phages (short for bacteriophages, or viruses that infect bacteria) can use iron as a “Trojan Horse” to gain access to host siderophore-bound iron receptors for infection. …

Structural And Functional Studies On 4-Hydroxy- Tetrahydrodipicolinate Reductase: Potential Drug Target In Bacteria, Swanandi Pote

Theses and Dissertations

Antimicrobial resistance has become an alarming public health concern since early 2000’s. Infections caused by multidrug resistant bacteria not only increase the mortality rate but also increase the economic burden globally. One approach to alleviate this issue is to find novel drug targets. In this regard, the bacterial lysine biosynthesis pathway provides several targets that may be used for design of antimicrobial compounds. Bacteria use lysine or meso-diaminopimelate to crosslink the peptidoglycan monomers in the bacterial cell wall. As such, we hypothesize that blocking this pathway will induce defects in the bacterial cell wall that are similar to those …

Staphylococcus Aureus Evasion Of The Innate Immune System, James Paul Grayczyk

Dissertations

Upon entry into the host, pathogens must overcome innate immunity in order to cause disease. The innate immune system represents a fast-acting initial line of defense to prevent infection. In order to withstand innate defenses, bacterial pathogens like the Gram-positive bacterium Staphylococcus aureus, produce a wide array of virulence factors that can inhibit innate immune cell recruitment and antimicrobial activity, or directly target and kill phagocytic leukocytes thereby facilitating pathogenesis. Infection with S. aureus can cause disease in virtually any tissue site and is a significant burden to human health. In this dissertation, we sought to understand how S. aureus …

The Effect Of Various Vinegars On Infectious Diseases And Body Metabolism, Alexandria Hutchins

Undergraduate Honors College Theses 2016-

Regular vinegar and apple cider vinegar have historically been used as home remedies to cure illness and diseases; however, not enough empirical research has been done to substantiate these assertions. This thesis will discuss the different ways that various vinegar forms affect one’s body metabolism, and the effect that they have on infectious diseases. This is an important topic to examine because of the growing number of infectious diseases. Vinegar contains polyphenols, which display antioxidant qualities in the body. Polyphenols found in the acetic acid of vinegar also inhibit microbial growth. This microbial growth is usually controlled by antimicrobials; however …

Fragile Oceans, Synthetic Flotsam And Microbial Collaboration – Explorations In The Visual Communication Of The Plastic Crisis, Ivan Langesfeld

Pomona Senior Theses

Scientific evidence that the ocean plastic crisis is larger in scale and more sinister than previously thought continues to mount, but the rate of plastic production is only rising. What will it take to decisively turn the tide against plastic? We need scientists, politicians, and industry changemakers to continue producing knowledge and positive change in the industry, but we need to go further still. This thesis explores art as an alternative visual communication strategy with the capacity to encourage curiosity, empathy, and positive engagement with the issue of ocean plastics. The series of work explores bacterial bioluminescence as an artistic …

The Gut Microbiome: Is Fecal Matter Microbial Composition A Proxy For Intestinal Microbial Composition In Studies Of The Microbiome, Enique Reyes

All Master's Theses

As many health phenomena seem to be affected directly and indirectly by the microbiome, gut microbiome research has increased in the last decade. Issues such as allergies, cancer, obesity, and other health complications have been shown to be influenced by the microbiome. Most of gut microbiome research is done by collecting and sequencing the DNA of the microbiome of the fecal matter from model organisms or human subjects. Studies that use this method of sample collection and analysis assume that fecal matter microbiomes are similar to intestinal microbiomes, and that it can be used as a proxy. At present, no …

Structure/Function Analysis Of Fega And Fhua In Bradyrhizobium Sp., Alexander James Herd

Senior Honors Projects, 2010-2019

Bradyrhizobium japonicum is a Gram-negative soil bacterium commonly known for its agriculturally significant mutualistic relationship with soybean. In this symbiosis, the bacteria and plant undergo complex molecular signaling characterized by sent and received signals resulting in the formation of infection threads and root nodules. This research aimed to compare two related bacterial outer membrane proteins, FegA and FhuA, associated with the molecular signaling between the bacteria and plant. Previous work has led to the hypothesis that the N-terminal domain (NTD) of FegA in B. japonicum is needed for a functional symbiosis to occur. Recombinant bacterial strains expressing altered FegA proteins …

Cropping Sequence Affects Subsequent Soybean Yield, Soil Microbiome And Soil Health, Izzet Bulbul

Electronic Theses and Dissertations

Rotation is an important cultural practice that farmers use to manage crop growth and diseases. Diversified crop rotations directly affect plant residue inputs that may enrich specific groups of microbes that form beneficial associations with the following crop. At two field sites, yield differences were observed in soybeans planted after the following four long-term (14 year) crop sequences: continuous corn (CC), corn (Zea mays)/corn/soybean (Glycine max) (CCS), corn/soybean/corn (CSC), soybean/corn/soybean (SCS). Soybean yields were in decreasing order, CC>CCS>CSC>SCS, and the yield differences could not be explained by soil chemical and physical properties previously …

Evaluation Of Colostrum On An Immunological And Microbiological Level And Its Relation To Calf Health: A Case Study Of Calves At Uvm Miller Research Center, Brooke Ann Pietrafesa

UVM Patrick Leahy Honors College Senior Theses

The objective of this study was to evaluate the colostrum fed to calves at the UVM Miller Research Center on an immunological and bacteriological level as well as to explore the relationship between these factors and the health of the calves. Colostrum samples fed to twelve calves during their first and second feedings were collected and evaluated using a colostrometer, Brix refractometer, and were also plated on 3M Petrifilm plates. During the study, the weights of the calves and their rectal temperatures were also recorded. Of the 18 colostrum samples, 7 of the Brix refractometer readings did not match the …