Other Microbiology Commons^™

Mutational Analysis Of Domain Functions In The Yeast Decapping Enzyme Dcp2, Jellisa Ewan, Ambro Van Hoof

Dissertations and Theses (Open Access)

In yeast, the major mRNA decay pathway involves deadenylation of the 3’ poly-A tail, followed by decapping of the 5’ m7Gppp cap and subsequent 5’ to 3’ degradation or 3’ to 5’ degradation. This is carried out by Pan2/Pan3 and Ccr4/Not deadenylases, the decapping enzyme Dcp2, and Xrn1 and  RNA exosome exoribonucleases, respectively. The eukaryotic mRNA decapping enzyme complex, Dcp1/Dcp2, is essential in yeast, and deletion of either gene is lethal. However, the deadenylases that act upstream and the 5’ exoribonuclease that act downstream of the decapping step are not, even though they are all highly conserved with no known …

Mobile Genetic Elements Shape Microbial Diversity And Functions In Thawing Permafrost Soils, Jiarong Guo, Samuel T. N. Aroney, Guillermo Domínguez-Huerta, Derek Smith, Dean Vik, Carlos Owusu-Ansah, Akbar Adjie Pratama, Sergei Solonenko, Funing Tian, Cristina Howard-Varona, Zhi-Ping Zhong, Aminata Fofana, Garrett J. Smith, Suzanne B. Hodgkins, Dylan Cronin, Isogenie Field Teams 2010–2017, 2019, Emerge Coordinators, Ben J. Woodcroft, Gene W. Tyson, Virginia I. Rich, Matthew B. Sullivan, Simon Roux, Sarah C. Bagby, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Ecosystems are shaped by communities of microorganisms whose niches and impacts depend on functional profiles influenced by gene gains and losses. Culture-based experiments demonstrate that mobile genetic elements (MGEs) can mediate gene flux, but quantitative understanding of these dynamics in natural systems remains limited. Here we develop and apply a systematic, meta-omic framework to investigate MGEs in a complex natural system using an 8-year soil time series collected at Stordalen Mire, in Sweden’s thawing permafrost margin. In this climate-critical peatland, we identify ~2.1 million MGE recombinases across 89 microbial phyla and assess ecological distributions, affected functions, past mobility and current …

Closing The Gaps: Reforming Maryland Controls On Veterinary Antimicrobial Distribution, Samantha Capaldo, Kerry Mcclaughry

Journal of Food Law & Policy

Antimicrobials have been used in livestock and other food animals in the United States (“U.S.”) since the late 1940s. An antimicrobial is “[a]ny natural, synthetic, or semisynthetic substance that can eradicate or prevent the growth of microbes,” including “[a]ntibacterial, antifungal, antiparasitic, and antiviral medications.” Antimicrobial use in food animals is subject to a complex statutory and regulatory framework at both the state and federal levels. Antimicrobial use in food animals has been widely criticized for contributing to antimicrobial-resistant bacterial infections in humans. In response to this criticism, the U.S. Food and Drug Administration (“FDA”) and several states, including Maryland, have …

Promiscuous Mutualisms: John Dupré And The Centrality Of Symbiosis In The Living World, Thomas Pradeu

Presidential Fellows Articles and Research

My goal in this chapter is to show that symbiosis, especially symbiotic interactions between ‘macrobes’ (non-microbial organisms) and microbes, is a central topic in John Dupré’s work. This topic is undeniably one of the topics by which Dupré has gained wide recognition among practicing scientists, in addition to his recognition within the philosophical community. I spell out why symbiosis has turned out to be a sort of ideal trope for Dupré, as it encapsulates many of his main personal themes—from promiscuous realism to process ontology. I then show that immunology offers one interesting and complementary entry point into microbial symbiosis …

The Impact Of Glucose Exposure On Organic Cation Transporters (Oct) Function In A Corneal Epithelial Cell Line, David A. Garza

Theses & Dissertations

Organic cation transporters (OCT) facilitate the movement of neurochemicals and medications, contribute to the removal of cellular waste, and facilitate neuronal communication. Three subtypes of these high-capacity, low-affinity transporters (OCT1, OCT2, and OCT3) are differently expressed in peripheral tissues such as the liver, kidneys, as well as the central nervous system. OCTs are also expressed in ocular tissues. Chronic hyperglycemia is a complication commonly associated with diabetes that can lead to ocular diseases such as diabetic keratopathy, which affects the cornea. In this project, we expose immortalized human corneal epithelial cells (HCE-S) to various glucose concentrations to study their impact …

Donor And Recipient Microbiome Interactions Determine Functional Outcomes Of Fecal Microbiota Transplantation For Clostridioides Difficile Infection, Sophie A. Millard

All Dissertations

Clostridioides difficile is a major cause of healthcare-associated diarrhea. Infection typically occurs after antibiotic treatment disrupts the gut microbiome, allowing C. difficile to colonize and produce toxins leading to disease (CDI). Standard antibiotic treatments can resolve acute infection but frequently lead to recurrence, highlighting the need for alternative strategies that restore the gut ecosystem. Fecal microbiota transplantation (FMT), the transfer of stool from a healthy donor, has emerged as an effective therapy for recurrent C. difficile infection (rCDI). Understanding the mechanisms underlying the success of FMT for treatment of rCDI could lead to safer, more defined microbial mixtures.

This dissertation …

Maintaining And Axenizing Live Cyanobacterial Cultures For Bacterial Genome Sequencing, Yufei Wang, Louisa Acquah

SACAD: Scholarly Activities

Harmful cyanobacterial blooms are an

increasing concern in western Kansas, yet the

bloom-forming species in this region remain

poorly characterized. In this study, we

established and maintained axenic

cyanobacterial cultures to support future

genomic and ecological investigations. By

ensuring low contamination levels and stable

growth conditions, this work provides a

foundation for downstream analyses of bloom-

forming cyanobacteria. It contributes to a better

understanding of freshwater ecosystem health

in western Kansas.

Decoupling Of Reproduction And Lifespan Trade-Off In Caenorhabditis Elegans Through Microbial Programming, Nora M. Villafuerte

LSU Master's Theses

The microbiome is increasingly recognized as a major regulator of host physiology. Using the Caenorhabditis elegans model, we investigated how natural commensal bacteria modulate host reproduction and lifespan through internal egg hatching, a phenotype in which retained embryos hatch within the maternal body. Screening strains from the CeMbio collection identified four focal strains Ochrobactrum BH3, Lelliottia JUb66, Pantoea BIGb0393, and Enterobacter CEent1 that significantly increased internal egg hatching during the late reproductive period. This contrasts with pathogenic bacteria, which induce early-onset internal egg hatching. Across the focal strains, worms exhibited reduced total brood size but an expanded reproductive window relative …

Exploring Alkaline Protease Activity Of Bacillus Strain Isolated From Sidon Dumpsite Lebanon, Zahra Farroukh, Dalia El-Badan, Jamilah Borjac

BAU Journal - Science and Technology

Proteases are crucial hydrolytic enzymes present in all organisms, performing essential physiological and industrial tasks. This study was conducted to screen and isolate protease-producing bacteria from soil and water samples collected from Sidon dumpsite in Lebanon. Bacterial samples were cultured onto skim milk agar medium to identify the alkaline protease-producing ones. In this study, we report on the partial purification and characterization of one of the isolated alkaline protease-producing bacteria. The bacterium was identified as Bacillus subtilis Z3 based on 16S rRNA sequencing. The molecular weight of the partially purified protease was approximately 55 kDa, estimated by sodium dodecyl sulphate …

Characterization Of The Human Thnatomicrobiome By Decomposition Stage Through Bioinformatic And Meta Data Analysis, Ashton C. Laughlin

Biology Theses

Estimating the postmortem interval (PMI) is one of the most crucial factors in forensic death investigations. Recent advances in forensic microbiology have led to increased interest in using the study of the human postmortem microbiome, or “thanatomicrobiome,” to improve PMI estimates. In addition to current PMI estimation techniques, microbial community succession could serve as a valuable tool in estimating PMI. Further research is needed to develop a comprehensive understanding of the human postmortem microbiome. The purpose of this study is to contribute to the expansion of this tool by reviewing the current literature and analyzing previously published data using the …