Life Sciences Commons^™

Effect Of Biochanin A On The Rumen Microbial Community Of Holstein Steers Consuming A High Fiber Diet And Subjected To A Subacute Acidosis Challenge, Brittany E. Harlow, Michael D. Flythe, James L. Klotz, David L. Harmon, Glen E. Aiken

Animal and Food Sciences Faculty Publications

Subacute rumen acidosis (SARA) occurs when highly fermentable carbohydrates are introduced into the diet, decreasing pH and disturbing the microbial ecology of the rumen. Rumen amylolytic bacteria rapidly catabolize starch, fermentation acids accumulate in the rumen and reduce environmental pH. Historically, antibiotics (e.g., monensin, MON) have been used in the prevention and treatment of SARA. Biochanin A (BCA), an isoflavone produced by red clover (Trifolium pratense), mitigates changes associated with starch fermentation ex vivo. The objective of the study was to determine the effect of BCA on amylolytic bacteria and rumen pH during …

Type I Topoisomerases As Potential Targets For Therapeutics, Ahmed Seddek

FIU Electronic Theses and Dissertations

DNA topoisomerases are universal enzymes that control the topological features of DNA in all forms of life. This study aims to find potential inhibitors of some of the DNA topoisomerases in bacteria and humans that can be developed into potential therapeutics.

The first aim of this study is to find potential inhibitors of bacterial topoisomerase I that can be developed into antibiotics. There is an urgent need to develop novel antibiotics to overcome the world-wide health crisis of antimicrobial resistance. Virtual screening and biochemical assays were combined to screen thousands of compounds for potential inhibitors of bacterial topoisomerase I. NSC76027 …

Characterizing The Diversity Of Cluster R Prophage In Mycobacterium Abscessus, Colin Welch

Honors College

Mycobacterium abscessus is a mycobacterial pathogen responsible for pulmonary and disseminated infections in susceptible individuals and often is resistant to all antibiotic therapies, with cure rates ranging from 25% to 58% (Degiacomi et al., 2019).Investigating the mechanisms of extensive resistance in M. abscessus lends opportunities to develop more effective treatments. Prophage, viral sequences integrated into bacterial genomes, contribute to virulence and fitness in many bacterial pathogens including Escherichia coli O157:H7 and Vibrio cholerae (Fortier & Sekulovic, 2013). Yet, prophage in pathogenic mycobacteria are not well understood or studied. Recent work has demonstrated that the Mycobacterium chelonae prophage, McProf can function …

Characterizing Mab Cluster R Prophage Of Pathogen Mycobacterium Abscessus (Mab), Madeline Kimble

Honors College

Mycobacterium abscessus (Mab) is an emerging pathogen that can cause pulmonary, skin and disseminating infections. It is one of the most drug-resistant pathogens and infections typically result in high morbidity and mortality. Understanding mechanisms of antibiotic resistance is critical for developing more effective treatments. Prophage, integrated viral genomes, are known to contribute to bacterial virulence and antibiotic resistance, yet Mab prophages remain largely uncharacterized.My research aims to characterize the diversity of the novel cluster MabR prophage genomes. The Molloy lab has demonstrated that the prophage McProf increases mycobacterial resistance to antibiotics. Using the McProf prophage genome sequence, we probed the …

Why Do Antibiotics Exist?, Fabrizio Spagnolo, Monica Trujillo, John J. Dennehy

Publications and Research

In the struggle with antibiotic resistance, we are losing. There is now a serious threat of moving into a postantibiotic world. High levels of resistance, in terms of both frequency and strength, have evolved against all clinically approved antibiotics worldwide. The usable life span of new clinically approved antibiotics is typically less than a decade before resistance reaches frequencies so high as to require only guarded usage. However, microbes have produced antibiotics for millennia without resistance becoming an existential issue. If resistance is the inevitable consequence of antibiotic usage, as has been the human experience, why has it not become …

Evidence For Continental-Scale Dispersal Of Antimicrobial Resistant Bacteria By Landfill-Foraging Gulls, Christina A. Ahlstrom, Mariëlle L. Van Toor, Hanna Woksepp, Jeffrey C. Chandler, John A. Reed, Andrew B. Reeves, Jonas Waldenström, Alan B. Franklin, David C. Douglas, Jonas Bonnedahl, Andrew M. Ramey

United States Department of Agriculture Wildlife Services: Staff Publications

Anthropogenic inputs into the environment may serve as sources of antimicrobial resistant bacteria and alter the ecology and population dynamics of synanthropic wild animals by providing supplemental forage. In this study, we used a combination of phenotypic and genomic approaches to characterize antimicrobial resistant indicator bacteria, animal telemetry to describe host movement patterns, and a novel modeling approach to combine information fromthese diverse data streams to investigate the acquisition and long-distance dispersal of antimicrobial resistant bacteria by landfill-foraging gulls. Our results provide evidence that gulls acquire antimicrobial resistant bacteria from anthropogenic sources, which they may subsequently disperse across and between …

Differing Alterations Of Odor Volatiles Among Pathogenic Stimuli, Patrick Millet, Talia Martin, Maryanne Opiekun, Gary K. Beauchamp, Bruce A. Kimball

United States Department of Agriculture Wildlife Services: Staff Publications

Alterations of the volatile metabolome (the collection of volatiles present in secretions and other emanations) that occur in response to inflammation can be detected by conspecifics and chemometric analyses. Using a model system where mouse urinary metabolites are altered by treatment with lipopolysaccharide (found in the outer cell membrane of gram-negative bacteria), we hypothesized that alteration of body odor volatiles will vary according to the pathogen responsible for inducing the inflammation. We tested this hypothesis by treating mice with different immunogens that engage different immune signaling pathways. Results suggest that alterations of body odor volatiles resulting from inflammation do contain …