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Image-Based Microbiome Profiling Differentiates Gut Microbial Metabolic States, Sarwesh Rauniyar 2021 Illinois State University

Image-Based Microbiome Profiling Differentiates Gut Microbial Metabolic States, Sarwesh Rauniyar

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.


The Role Of Low-Molecular Weight Fungal Metabolites In Eutypa Dieback Grapevine Trunk Disease, Dana Sebestyen 2021 University of Massachusetts Amherst

The Role Of Low-Molecular Weight Fungal Metabolites In Eutypa Dieback Grapevine Trunk Disease, Dana Sebestyen

Masters Theses

Eutypa dieback, one of several grapevine trunk diseases (GTDs), is of serious concern to the grape industry globally. This disease is caused by the fungus Eutypa lata but it is often seen in consortia growth with Phaeoacremonium minimum and Phaeomoniella chlamydospora. It is vital to understand the mechanisms for how this disease functions to develop control measures to combat it. Brown rot fungi are able to use a complex of low molecular weight (LMW) metabolites to induce a Fenton reaction to deconstruct woody tissue. These metabolites are part of a chelator mediated Fenton (CMF) chemistry that produces reactive oxygen species ...


The Role Of The Msaabcr Operon In Cell Wall Integrity And Programmed Cell Death During Biofilm Development, Bibek G C 2021 The University of Southern Mississippi

The Role Of The Msaabcr Operon In Cell Wall Integrity And Programmed Cell Death During Biofilm Development, Bibek G C

Dissertations

Staphylococcus aureus is an important human pathogen in both community and health care settings. Biggest challenges with S. aureus as a pathogen is its ability to acquire antibiotic resistance and produce robust biofilms. In this work, we investigated the nature of the cell wall defect in the msaABCR operon mutant in the Mu50 (VISA) and USA300 LAC methicillin-resistant Staphylococcus aureus (MRSA) strains. Results showed that msaABCR-mutant cells had decreased cell wall thickness and cell wall crosslinking in both strains. These defects are most likely due to increased murein hydrolase activity and/or nonspecific processing of murein hydrolases mediated by ...


How Acetylation Regulates Metabolic Enzyme Function During Environmental Shifts, Jared Canonigo 2021 University of Arkansas, Fayetteville

How Acetylation Regulates Metabolic Enzyme Function During Environmental Shifts, Jared Canonigo

Biological Sciences Undergraduate Honors Theses

Organisms such as Saccharomyces cerevisiae can regulate the mechanisms of proteins through post-translational modification. These modifications play a vital role in functional proteomic activity because they can regulate protein activity, localization, and interaction with other cellular molecules. Such modifications include phosphorylation, methylation, and acetylation. The metabolic mechanisms of yeast became of keen interest to our lab because our lab noticed many stress defense proteins were being acetylated during stress heat shock. Notably, Adh1p and Adh2p showed both an increase and a decrease in acetylation at two lysine residues (K315 and K314) overtime during heat shock respectively, though the exact function ...


Increasing Stress Tolerance In Saccharomyces Cerevisiae Using Lipocalin Genes, Ximena Leon 2021 University of Tennessee at Chattanooga

Increasing Stress Tolerance In Saccharomyces Cerevisiae Using Lipocalin Genes, Ximena Leon

Honors Theses

Saccharomyces cerevisiae is a microorganism that is commonly used in industries, but its productivity is significantly hindered by its inability to resist high stress levels found in industrial processes. By increasing stress tolerance in S. cerevisiae, its role in industrial processes could be maximized. The objective of this study is to determine if complementation of lipocalin genes into the wildtype and knockout strains of S. cerevisiae can increase stress tolerance against a variety of stressors. We identified the knockout yeast strains, ALD3, ALD4, PDX3, and ILV1, as being sensitive to various stressors including salinity, heat, oxidative, and osmotic stresses. Arabidopsis ...


Identification Of Proteins That Contribute To Yeast Heat Stress By Lysine Acetylation, Weijia Shi 2021 University of Arkansas, Fayetteville

Identification Of Proteins That Contribute To Yeast Heat Stress By Lysine Acetylation, Weijia Shi

Biological Sciences Undergraduate Honors Theses

Evidence is emerging that protein lysine acetylation may be a novel type of post-translational modification (PTM) contributing to the mechanisms of yeast heat stress responses. Proteomics studies including ours have identified over 1,000 acetylated proteins in the yeast proteomes that are composed of about 6,000 proteins. Our lab recently identified 596 proteins that underwent acetylation changes during heat shock by mass spectrometry. However, the role of lysine acetylation on specific residues of specific proteins in yeast thermotolerance remains largely unknown. This study selected 43 proteins from our lab’s previous work and examined their possible contributions to yeast ...


Pathogenicity Of Staphylococcus Agnetis Associated With Lame Broilers With Osteomyelitis, Sura Faris Salih Zaki 2021 University of Arkansas, Fayetteville

Pathogenicity Of Staphylococcus Agnetis Associated With Lame Broilers With Osteomyelitis, Sura Faris Salih Zaki

Graduate Theses and Dissertations

We developed High Resolution Melt Analysis (HERMA) as a rapid and reliable molecular diagnostic assay for the detection and identification of the main bacterial species recovered from the blood and lesions of bacterial chondronecrosis with osteomyelitis (BCO) from the lame broilers at the University of Arkansas poultry research farm. Also, the present study confirms that raising young birds on suspended wire flooring has been proved to successfully induce lameness attributable to BCO with birds being more susceptible to bacteraemia than those that were raised on litter flooring. The newly described pathogen, Staphylococcus agnetis, has been reported to be overrepresented in ...


B12: The T Cell Co-Receptor Cd5 Alters Mouse Behavior And Gut Microbiome Composition, Kyle Reaveley 2021 Brigham Young University

B12: The T Cell Co-Receptor Cd5 Alters Mouse Behavior And Gut Microbiome Composition, Kyle Reaveley

Annual Research Symposium

No abstract provided.


Yeasts Isolated From Traditional Brem Bali Show Stress Tolerance Phenotype Against Fermentation-Related Stresses, Audria Bayu Lenka, Rika Indri Astuti, Sri Listiyowati 2021 Department of Biology, Faculty of Mathematics and Natural Sciences, Institut Pertanian Bogor, Bogor 16680, Indonesia

Yeasts Isolated From Traditional Brem Bali Show Stress Tolerance Phenotype Against Fermentation-Related Stresses, Audria Bayu Lenka, Rika Indri Astuti, Sri Listiyowati

Makara Journal of Science

The search for microbes, primarily yeasts with unique characters such as the tolerance against fermentation-related-stresses, is gaining significant interest nowadays. Traditionally made alcoholic beverages can be used as sources for such yeasts, given that during fermentation and storage, microbes may develop stress tolerance responses leading to naturally stress-tolerant yeast strains. In this study, we used an alcoholic beverage, that is, Brem Bali, as the source of potential yeast isolates. We isolated nine yeast isolates from two traditional Brem Bali products. All isolates showed tolerance against high glucose stress (40–50%) and sensitivity against high-temperature stress (37–50 °C). Notably, isolate ...


Mfd Affects Global Transcription And The Physiology Of Stressed Bacillus Subtilis Cells, Holly Anne Martin, Anitha Sundararajan, Tatiana S. Ermi, Robert Heron, Jason Gonzales, Kaiden Lee, Diana Anguiano-Mendez, Faye Schilkey, Mario Pedraza-Reyes, Eduardo A. Robleto 2021 University of Nevada, Las Vegas

Mfd Affects Global Transcription And The Physiology Of Stressed Bacillus Subtilis Cells, Holly Anne Martin, Anitha Sundararajan, Tatiana S. Ermi, Robert Heron, Jason Gonzales, Kaiden Lee, Diana Anguiano-Mendez, Faye Schilkey, Mario Pedraza-Reyes, Eduardo A. Robleto

Life Sciences Faculty Publications

© Copyright © 2021 Martin, Sundararajan, Ermi, Heron, Gonzales, Lee, Anguiano-Mendez, Schilkey, Pedraza-Reyes and Robleto. For several decades, Mfd has been studied as the bacterial transcription-coupled repair factor. However, recent observations indicate that this factor influences cell functions beyond DNA repair. Our lab recently described a role for Mfd in disulfide stress that was independent of its function in nucleotide excision repair and base excision repair. Because reports showed that Mfd influenced transcription of single genes, we investigated the global differences in transcription in wild-type and mfd mutant growth-limited cells in the presence and absence of diamide. Surprisingly, we found 1,997 ...


Roles Of Non-Frankia Bacteria In Root Nodule Formation And Function In Alnus Sp., Kelsey Christine Mercurio 2021 University of New Hampshire, Durham

Roles Of Non-Frankia Bacteria In Root Nodule Formation And Function In Alnus Sp., Kelsey Christine Mercurio

Honors Theses and Capstones

Plant roots are home to a wide variety of beneficial microbes; understanding and optimizing plant-microbe interactions may be critical to enhance global food security in a sustainable, equitable way. With the help of their nitrogen-fixing bacterial partner, Frankia, actinorhizal plants form symbiotic root nodules and play important roles in agroforestry and land reclamation. However, Frankia does not live alone in nodules, and the other microbial residents may contribute to nodule formation and function. We collected root nodules from alder trees (Alnus sp.) in 2018 and 2019, then isolated DNA and individual bacterial strains to characterize the nodule microbial community. Of ...


Nutritional Effects On The Gut Microbiome & The Brain-Gut Axis: Unlocking The Therapeutic And Preventative Potential Of Nutrition For Gut Dysbiosis Associated Diseases, Sarah Freund 2021 Iowa State University

Nutritional Effects On The Gut Microbiome & The Brain-Gut Axis: Unlocking The Therapeutic And Preventative Potential Of Nutrition For Gut Dysbiosis Associated Diseases, Sarah Freund

Creative Components

Diet plays a pivotal role in the overall health of an individual. Not only does it help carry out and regulate certain physiological functions, but it also can determine the composition of the gut microbiome. While the microorganisms that make up the gut microbiome vary between individuals and can be dependent on different environmental factors, there has been evidence to suggest that the type of bacteria that colonize the gut can correlate to better overall health. When the GI microbiome is upset or suddenly changes it results in gut dysbiosis, a condition that correlates to the presence of certain diseases ...


Micro-Physiological Models To Mimic Mucosal Barrier Complexity Of The Human Intestine In Vitro, Abhinav Sharma 2020 University of Massachusetts Amherst

Micro-Physiological Models To Mimic Mucosal Barrier Complexity Of The Human Intestine In Vitro, Abhinav Sharma

Doctoral Dissertations

The mucosal barrier in the intestine is vital to maintain selective absorption of nutrients while protecting internal tissues and maintaining symbiotic relationship with luminal microbiota. This bio-barrier consists of a cellular epithelial barrier and an acellular mucus barrier. Secreted mucus regulates barrier function via in situ biochemical and biophysical interaction with luminal content that continually evolves during digestion and absorption. Increasing evidence suggests that a mucus barrier is indispensable to maintain homeostasis in the gastrointestinal tract. However, the importance of mucus barrier is largely underrated for in vitro mucosal tissue modeling. The major gap is the lack of experimental material ...


Investigating Microbial And Host Factors That Modulate Severity Of Clostridioides Difficile Associated Disease, Armando Lerma 2020 University of Nebraska-Lincoln

Investigating Microbial And Host Factors That Modulate Severity Of Clostridioides Difficile Associated Disease, Armando Lerma

Dissertations, Theses, & Student Research in Food Science and Technology

Clostridioides difficile is recognized as one of the most important pathogens in hospital and community healthcare settings. The clinical outcome of infection of toxigenic C. difficile infection (CDI) ranges from asymptomatic colonization to fulminant pseudomembranous colitis and death. In recent studies, it has been suggested that a high proportion of nosocomial CDI cases are transmitted from asymptomatic carriers which might be acting as infection reservoirs. Understanding what causes the different responses to infection could lead to the development of novel prevention and treatment strategies. Although several explanations have been proposed to explain variations in susceptibility, understanding of the exact mechanisms ...


Metabolic Interactions In Microbial Communities, Elizabeth A. Shank 2020 University of Massachusetts Medical School

Metabolic Interactions In Microbial Communities, Elizabeth A. Shank

University of Massachusetts Medical School Publications

The Shank laboratory studies the chemical and physical interactions of microbes with each other and their hosts. Microbes live everywhere, and their activities can have profound impacts on their hosts as well as on ecosystem‐level processes. How microbes interact within these communities, however, remains largely unknown. We are fascinated by the idea that microbes are able to generate and secrete chemical cues (known as specialized or secondary metabolites) that can act as interspecies signals to influence the physiology and metabolism of their microbial neighbors, and thus contribute to the stability and functioning of complex microbial communities. Our research dissects ...


Reverse Engineering Of Fatty Acid-Tolerant Escherichia Coli Identifies Design Strategies For Robust Microbial Cell Factories, Yingxi Chen, Erin E. Boggess, Efrain Rodriguez Ocasio, Aric Warner, Lucas Kerns, Victoria Drapal, Chloe Gossling, Wilma Ross, Richard L. Gourse, Zengyi Shao, Julie Dickerson, Thomas J. Mansell, Laura R. Jarboe 2020 Iowa State University and Chinese Academy of Sciences

Reverse Engineering Of Fatty Acid-Tolerant Escherichia Coli Identifies Design Strategies For Robust Microbial Cell Factories, Yingxi Chen, Erin E. Boggess, Efrain Rodriguez Ocasio, Aric Warner, Lucas Kerns, Victoria Drapal, Chloe Gossling, Wilma Ross, Richard L. Gourse, Zengyi Shao, Julie Dickerson, Thomas J. Mansell, Laura R. Jarboe

Chemical and Biological Engineering Publications

Adaptive laboratory evolution is often used to improve the performance of microbial cell factories. Reverse engineering of evolved strains enables learning and subsequent incorporation of novel design strategies via the design-build-test-learn cycle. Here, we reverse engineer a strain of Escherichia coli previously evolved for increased tolerance of octanoic acid (C8), an attractive biorenewable chemical, resulting in increased C8 production, increased butanol tolerance, and altered membrane properties. Here, evolution was determined to have occurred first through the restoration of WaaG activity, involved in the production of lipopolysaccharides, then an amino acid change in RpoC, a subunit of RNA polymerase, and finally ...


The Physiology And Evolution Of Selenite Respiration In Bacteria, Michael Wells 2020 Duquesne University

The Physiology And Evolution Of Selenite Respiration In Bacteria, Michael Wells

Electronic Theses and Dissertations

The selenium oxyanions selenate (Se(VI)) and selenite (Se(IV)) can be utilized by some bacteria and archaea as terminal electron acceptors in anaerobic respiration. Se(VI) and Se(IV) respiration is mediated by a phylogenetically and ecologically diverse array of organisms, suggesting that selenium respiration is ubiquitous in natural environments. Several respiratory Se(VI) reductases have been characterized in bacteria, revealing that Se(VI) respiration has evolved independently several times in this domain. Se(IV) respiration, in contrast, has yet to be characterized. I have purified and characterized the first respiratory Se(IV) reductase from Bacillus selenitireducens MLS10. The ...


Linearized Siderophore Products Secreted Via Macab Efflux Pump Protect Salmonella Enterica Serovar Typhimurium From Oxidative Stress, L M. Bogomolnaya, Ronak Tilvawala, J. R. Elfenbein, J. D. Cirillo, H. L. Andrews-Polymenis 2020 Texas A&M University

Linearized Siderophore Products Secreted Via Macab Efflux Pump Protect Salmonella Enterica Serovar Typhimurium From Oxidative Stress, L M. Bogomolnaya, Ronak Tilvawala, J. R. Elfenbein, J. D. Cirillo, H. L. Andrews-Polymenis

Open Access Publications by UMass Chan Authors

Nontyphoidal salmonellae (NTS) are exposed to reactive oxygen species (ROS) during their residency in the gut. To survive oxidative stress encountered during infection, salmonellae employ several mechanisms. One of these mechanisms involves the multidrug efflux pump MacAB, although the natural substrate of this pump has not been identified. MacAB homologs in pseudomonads secrete products of nonribosomal peptide synthesis (NRPS). In Salmonella enterica serovar Typhimurium, the siderophore enterobactin is produced by NRPS in response to iron starvation and this molecule can be processed into salmochelin and several linear metabolites. We found that Salmonella mutants lacking the key NRPS enzyme EntF are ...


Dietary Soluble And Insoluble Fiber With Or Without Enzymes Altered The Intestinal Microbiota In Weaned Pigs Challenged With Enterotoxigenic E. Coli F18, Qingyun Li, Xiyu Peng, Eric R. Burrough, Orhan Sahin, Stacie A. Gould, Nicholas K. Gabler, Crystal L. Loving, Karin Dorman, John F. Patience 2020 Iowa State University

Dietary Soluble And Insoluble Fiber With Or Without Enzymes Altered The Intestinal Microbiota In Weaned Pigs Challenged With Enterotoxigenic E. Coli F18, Qingyun Li, Xiyu Peng, Eric R. Burrough, Orhan Sahin, Stacie A. Gould, Nicholas K. Gabler, Crystal L. Loving, Karin Dorman, John F. Patience

Animal Science Publications

Post-weaning diarrhea caused by enterotoxigenic E. coli (ETEC) causes significant economic losses for pig producers. This study was to test the hypotheses that an ETEC challenge disrupts intestinal microbial homeostasis and the inclusion of dietary soluble (10% sugar beet pulp) or insoluble fiber (15% corn distillers dried grains with solubles) with or without exogenous carbohydrases will protect or restore the gut microbial homeostasis in weaned pigs. Sixty crossbred piglets (6.9 ± 0.1 kg) were blocked by body weight and randomly assigned to one of six treatments (n = 10), including a non-challenged control (NC), ETEC F18-challenged positive control (PC), ETEC-challenged ...


Effects Of An F18 Enterotoxigenic Escherichia Coli Challenge On Growth Performance, Immunological Status, And Gastrointestinal Structure Of Weaned Pigs And The Potential Protective Effect Of Direct-Fed Microbial Blends, Spenser L. Becker, Qingyun Li, Eric R. Burrough, Danielle Kenne, Orhan Sahin, Stacie A. Gould, John F. Patience 2020 Iowa State University

Effects Of An F18 Enterotoxigenic Escherichia Coli Challenge On Growth Performance, Immunological Status, And Gastrointestinal Structure Of Weaned Pigs And The Potential Protective Effect Of Direct-Fed Microbial Blends, Spenser L. Becker, Qingyun Li, Eric R. Burrough, Danielle Kenne, Orhan Sahin, Stacie A. Gould, John F. Patience

Animal Science Publications

The objective of this experiment was to investigate the impact of an F18 enterotoxigenic Escherichia coli (ETEC) challenge on growth performance, aspects of intestinal function, and selected immune responses of piglets, as well as to evaluate potential protective effects of direct-fed microbial (DFM) blends. Seventy-two weaned piglets (6.4 ± 0.2 kg body weight [BW]; ~21 d of age) were assigned to one of four treatments: 1) NC: Nonchallenged (n = 10), 2) positive challenged control (PC): F18 ETEC-challenged (n = 10), 3) PC + DFM1 (n = 8; three strains of Bacillus amyloliquefaciens; 7.5 × 105 colony-forming units [cfu]/g), or 4) PC ...


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