Microbiology Commons^™

Molecular Detection Of Pathogenic Leptospira And Microbial Source Tracking Of Fecal Pollution In San Juan, Puerto Rico, Taylor I. Chapman

Biology Theses

Leptospirosis, caused by pathogenic Leptospira, is endemic to tropical regions. Leptospira is released into the environment through the secretion of urine from animals, making it easily transmissible through water sources. The estuarian environment surrounding the area of San Juan, Puerto Rico and its high density of urban development creates ideal conditions for transmission of Leptospirosis. The goal of this study was to determine the presence of Leptospira in these surface waters and use Microbial Source Tracking (MST) to identify the possible source of pathogenic Leptospira. Eighty-seven water samples were collected during the dry (44) and wet (43) seasons. …

Uncovering Potential Biofilm Modulators, Liliana Margent

Theses and Dissertations

Biofilms have negative and positive impacts depending on the context they develop. In this work, I optimized a biofilm assay to evaluate the effect of three different types of compounds indole derivatives, 2,5 Diketopiperazines, and 12-hydroxystearic acid on the biofilm formation of E. coli.

Lipoxin A 4 (Lxa 4 ) Promotes Reduction And Antibiotic Efficacy Against Pseudomonas Aeruginosa Biofilm, Julianne M. Thornton, Jean Walker, Prem Yugandhar Kadiyam Sundarasivarao, Bernd Spur, Ana Rodriguez, Kingsley Yin

Rowan-Virtua Research Day

Pseudomonas aeruginosa (P aeruginosa) is an opportunistic bacterium commonly found in wound infections and airways of cystic fibrosis patients P aeruginosa readily forms biofilms which can reduce the efficacy of antibiotics used to eradicate the pathogen We have previously shown that a Specialized Pro resolving Mediator ( Lipoxin A 4 (LxA 4 is a quorum sensing inhibitor which can reduce P aeruginosa virulence In this study, we examined the direct actions of LxA 4 and RvD 2 on P aeruginosa biofilm formation and virulence gene expression The influence of LxA 4 on antibiotic efficacy and the combined effects on biofilm …

Profile Of Antimicrobial Susceptibility From Cattles’S Milk Isolates Suffering From Mastitis In District Lahore, Muhammad Imran, Iqra Rehman, Abdul Qayyum Khan Sulehria, Yasser Mustafa Butt, Abdul Majid Khan, Azizah Ziauddin

Journal of Bioresource Management

Mastitis is highly prevalent infection in cattle causing cost-effective loss in dairy milk production. Escherichia coli is the most frequently isolated bacteria causing mastitis worldwide. The current study was performed to investigate the mastitis prevalence and effect of different antibiotics against pathogens causing it. In sum, 216 milk samples were collected randomly including 108 each from both cows and buffaloes. These samples were subjected to Surf Field Mastitis Test for prevalence of mastitis that found 18.50% and 23.14% in buffaloes and cows respectively. Mastitis was more prevalent both in buffaloes and cows at the age of 9-10 years that was …

Sickness Behaviors Across Vertebrate Taxa: Proximate And Ultimate Mechanisms, Patricia C. Lopes, Susannah S. French, Douglas C. Woodhams, Sandra A. Binning

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

There is nothing like a pandemic to get the world thinking about how infectious diseases affect individual behavior. In this respect, sick animals can behave in ways that are dramatically different from healthy animals: altered social interactions and changes to patterns of eating and drinking are all hallmarks of sickness. As a result, behavioral changes associated with inflammatory responses (i.e. sickness behaviors) have important implications for disease spread by affecting contacts with others and with common resources, including water and/or sleeping sites. In this Review, we summarize the behavioral modifications, including changes to thermoregulatory behaviors, known to occur in vertebrates …

Genomics, Exometabolomics, And Metabolic Probing Reveal Conserved Proteolytic Metabolism Of Thermoflexus Hugenholtzii And Three Candidate Species From China And Japan, Scott C. Thomas, Devon Payne, Kevin O. Tamadonfar, Cale O. Seymour, Jian Yu Jiao, Senthil K. Murugapiran, Dengxun Lai, Rebecca Lau, Benjamin P. Bowen, Leslie P. Silva, Katherine B. Louie, Marcel Huntemann, Alicia Clum, Alex Spunde, Manoj Pillay, Krishnaveni Palaniappan, Neha Varghese, Natalia Mikhailova, I. Min Chen, Dimitrios Stamatis, T. B.K. Reddy, Ronan O’Malley, Chris Daum, Nicole Shapiro, Natalia Ivanova, Nikos C. Kyrpides, Tanja Woyke, Emiley Eloe-Fadrosh, Trinity L. Hamilton, Paul Dijkstra, Brian P. Hedlund

Life Sciences Faculty Research

Thermoflexus hugenholtzii JAD2 , the only cultured representative of the Chloroflexota order Thermoflexales, is abundant in Great Boiling Spring (GBS), NV, United States, and close relatives inhabit geothermal systems globally. However, no defined medium exists for T. hugenholtzii JAD2 and no single carbon source is known to support its growth, leaving key knowledge gaps in its metabolism and nutritional needs. Here, we report comparative genomic analysis of the draft genome of T. hugenholtzii JAD2 and eight closely related metagenome-assembled genomes (MAGs) from geothermal sites in China, Japan, and the United States, representing “Candidatus Thermoflexus japonica,” “Candidatus Thermoflexus tengchongensis,” and “Candidatus …

Diagnostic Approaches To Combat Antibiotic Resistance In Bacteria, Alexander Oliveri, Shade Smith, Anshul Anugu

Honors Theses

The threat of antibiotic resistance is a major problem faced by the healthcare field affecting millions of people and costing tens of thousands of lives annually. Of the potential ways to mitigate this issue the field of antibiotic resistance testing presents an opportunity for significant improvement and benefits. Several methods of such diagnostic processes can yield more informative results than the current commonly used Kirby-Bauer test. However, there are benefits and limitations to each method. In the context of a clinically relevant diagnostic for antibiotic resistance, the microarray platform exhibits the necessary breadth with opportunities to overcome some limitations with …

Purification Of Pcbp2 And Its Effect On The Formation Of Dna I-Motifs And Secondary Structures, Nathan Redden

Honors Theses

Several secondary, non-B forms of DNA are associated with the promoter regions of many oncogenes, including the intensely studied c-MYC gene that codes for a transcription factor. Two such secondary structures, G-quadruplexes, and i-motifs, have become topics of interest due to their prevalence within oncogenic promoters, as well as their potential accessibility for drug targeting. B-form DNA can adopt alternative structures under certain conditions. These alternative structures are favored when there is an asymmetric distribution of guanosine and cytosine on complimentary DNA strands. The strand rich in guanosine is able to form a quadruple stranded DNA complex termed a G-quadruplex. …

The Role Of Med31 And Med12 In Directing Adipogenesis Of Human Adult-Derived Mesenchymal Stem Cells, Joseph Straub

Master's Theses

Selective gene expression is crucial in maintaining the self-renewing and multipotent properties of stem cells. Mediator is a large, evolutionarily conserved, multisubunit protein complex that modulates gene expression by relaying signals from cell type-specific transcription factors to RNA polymerase II. In humans, this complex consists of 30 subunits arranged in four modules: head, middle, tail, and kinase. In our introduction, we show the state of the field of Mediator study with a focus on the critical kinase module. In the following chapters, we used siRNA knockdowns to investigate the roles of the highly-conserved core subunit MED31 and the kinase module …

Elucidating The Role Of The Msaabcr Operon In Persister Cells Formation And Stress Response In Staphylococcus Aureus, Shanti Pandey

Dissertations

Staphylococcus aureus is a major human pathogen that causes lethal systemic conditions such as infective endocarditis, osteomyelitis, sepsis and pneumonia. Chronic in nature, these diseases are often refractory to the antibiotic treatment. Such recalcitrance is mainly caused due to the presence of persister cells, which are a bacterial subpopulation that exhibits extreme, yet transient antibiotic tolerance accompanied by a transient halt in the growth. However, upon cessation of antibiotic treatment, resumption in growth of persister cells causes recurrence of infections and treatment failure, displaying tremendous clinical significance. In this study, we show the involvement of the msaABCR operon in persister …

Elevated Incidences Of Antimicrobial Resistance And Multidrug Resistance In The Maumee River (Ohio, Usa), A Major Tributary Of Lake Erie, Maitreyee Mukherjee, Leah Marie, Cheyenne Liles, Nadia Mustafa, George Bullerjahn, Terry J. Gentry, John P. Brooks

Faculty Publications

Maumee River, the major tributary in the western basin of Lake Erie, serves as one of major sources of freshwater in the area, supplying potable, recreational, and industrial water. In this study we collected water samples from four sites in the Maumee River Bay between 2016–2017 and E. coli was isolated, enumerated, and analyzed for antimicrobial resistance (AMR) and multidrug resistance (MDR). Strikingly, 95% of the total isolates were found to be resistant to at least one antibiotic. A very high resistance to the drugs cephalothin (95.3%), ampicillin (38.3%), tetracycline (8.8%), gentamicin (8.2%), ciprofloxacin (4.2%), cefoperazone (4%), and sulfamethoxazole (1.5%) …

Pseudo-Dumbbell And Dumbbell Rna Structures : Modulators Of Zika Virus Translation And Replication, Marissa Eileen Louis

Legacy Theses & Dissertations (2009 - 2024)

Upon its discovery in 1947, Zika virus has remained in the shadows until its re-emergence in 2015, where Zika virus wreaked havoc on the lives of mothers and their infants around the world. The pathologies related to this virus range from neurological defects, such as Guillain-Barré syndrome, and congenital birth defects, such as Congenital Zika Syndrome, spontaneous miscarriages and fetal demise.Since 2015, this virus has been largely studied, but secondary structure and function of RNA structures at the end of the 3’UTR, namely the pseudo-dumbbell and the dumbbell (DB) structures, remains elusive. Thus, this dissertation addresses several questions pertaining to …

Isolating Oral Bacterial Species From A Single Donor Through A Multi-Step Detection Method, Khalid Al-Lakhen

Legacy Theses & Dissertations (2009 - 2024)

The human oral microbiome is one of the most complex microbiome communities in the human body and its role in maintaining health is not fully understood. Previous research shows that the transition from health to disease is accompanied by changes in community abundance and structure. To fully understand the symbiotic relationship formed between bacterial species that leads to the formation of a functional healthy biofilm structure, we must study the various structural relationships and subsequent molecular interactions among individual species within the biofilm. In this thesis, I have isolated a pure bacteria species from a single donor's dental plaque and …

Characterization Of A Putative Helicase In Rifampicin Resistance Of Mycobacterium Abscessus:, Aavrati Saxena

Legacy Theses & Dissertations (2009 - 2024)

Mycobacterium abscessus (Mab), a non-tuberculous environmental mycobacterium is one of the emerging pathogens. The number of Mab infections has doubled in the past decade. It is also an opportunistic pathogen usually infecting immunocompromised individuals and causing numerous skin and soft tissue infections. It commonly causes lung infections in people who are already infected with one or other lung infections such as tuberculosis. The treatment of Mab infections is difficult because of its intrinsic resistance to most of the antibiotics available. This project studies Rifampicin (RIF) resistance in Mab, as RIF is a well-established treatment for other mycobacterial infections including tuberculosis, …

Developing A Microdialysis Sampling-Based Biofilm/Macrophage Co-Culture Model, Alda Diaz Perez

Graduate Theses and Dissertations

The host immune system and bacterial cells are known to interact during the human lifetime. Bacteria secrete a wide variety of signaling molecules, known as quorum sensing (QSC) molecules, that modulate the host immune system. While immune-biofilm interactions involve this chemical signaling network, the mechanisms through which this occurs are not well understood. This work aimed to develop a new method that can be used not only in vitro settings but also in vivo. The microdialysis sampling technique has widely been used in in vitro and in vivo settings in humans, mice, and rats for the collection of neuropeptides, cytokines, …

College Of Natural Sciences Newsletter, May 2021, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Volume 2, Issue 5.

Page 1 Dean's Message
Page 2 - 3 Awards & Recognition
Page 4 Research Spotlight: Dr. Xiaoyang Zhang
Page 5 Upcoming Retirements
Page 6 - 7 Geography Alumni Social, Recent Media Coverage
Page 8 Open PRAIRIE Data
Page 9 - 11 Spring 2021 Dean's List and Academic Recognitions

Construction And Analysis Of Three Multi-Partite Synthetic Microbial Communities, Alexander J. Lazzara, Jacob K. Fanning

Honors Theses

Microbial Communities are of interest to molecular biologists hoping to understand the nature of metabolic interactions between co-existing, or possibly mutualistic, organisms. These interactions are ubiquitous in nature, but understanding the molecular mechanisms involved remains challenging and not well understood. Here, we design three tri-partite microbial circuits based on possible interactions among involved microbes, which are discussed and may suggest mutualistic interactions. Carbon and nitrogen molecular pathways and the intracellular metabolism of each microbe is discussed. We present minimal growth media that will ensure that organisms utilize available resources, which may originate from metabolic processes in neighboring microbes, simulating a …

Evaluation Of Nickel Stress On Anabaena Cylindrica, Danielle L. Maragh

Seton Hall University Dissertations and Theses (ETDs)

Heavy metal contamination due to anthropogenic activities has steadily been on the rise over the past few decades. Cyanobacteria can thrive in water bodies that have been contaminated by heavy metal runoffs and are able to tolerate heavy metal stress even in relatively high concentrations. Cyanobacterial species can secrete toxins which can prove harmful to humans and life stock. Due to their high adaptation to heavy metal stress, understanding the potential mechanism behind their response may lead to solutions in curbing excessive cyanobacterial growth especially in water bodies that serves as sources of drinking water. Anabaena spp. is a genus …

Implementing Crispr-Cas9 Gene Editing System In Microbotryum., Stevana Reese Schauer

College of Arts & Sciences Senior Theses

Microbotryum dianthorum is a species of smut fungus which causes infection in plants in the Dianthus genus. The infection process is aided by small-secreted proteins known as effectors. Effectors may aid in the infection process because they are secreted by the fungus and can enter plant tissue, possibly to facilitate infection and/or manipulate the host. Thus, it is of interest to investigate the genes for these effectors to determine their role in the infection process. One method to study genes is through gene disruption, via the CRISPR/Cas9 gene editing system, but this has not yet been implemented in Microbotryum dianthorum …

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 …

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 heat stress responses. …

Contaminated Mycoscapes: Designing With Living Organisms, Maria Gutierrez, Elise Zilius

Architecture Senior Theses

The Anthropocene has stripped the planet of its resources, leaving behind an abundance of contamination. The built environment no longer meets the standards set by our turbulent planet. Humankind has lost the privilege of agency in design and construction. Construction methods have failed to evolve concurrently to the intense accumulation of waste; remaining firmly rooted in the materiality of the past, they have upheld architectural notions of stagnancy, cleanliness, and hygiene and ignore the rapidly changing conditions of the environment. This investigation uses contamination to fuel mycelial growth and construct emergent forms whilst executing remediation strategies for polluted sites of …

How Historic Shipwrecks Influence Dispersal Of Deep-Sea Microbiomes, Rachel Moseley

Master's Theses

This thesis investigates how historic shipwrecks potentially shape dispersal of deep-sea microbiomes. Processes impacting dispersal of microbiomes around artificial structures in the ocean and how they connect to other deep-sea habitats is unknown. Dispersal processes are explained for some macroorganisms by theories in ecology, specifically the Theory of Island Biogeography and the Wooden Stepping Stone hypothesis. These have not been investigated for microorganisms, and thus this work will probe if they are applicable to microbial biogeography in this habitat. Experiments were conducted to establish new “island-like” features in near proximity (25-125 m) to wooden-hulled historic shipwrecks in the northern Gulf …

Partial Expression Of The Vbss Gene In Rhizobium Leguminosarum Atcc 14479 And In-Silico Analysis Of The Vbs Gene Cluster In Various Microorganisms, Afreen Siddiqui

Undergraduate Honors Theses

Iron is extremely important for many organisms. Despite its abundancy, it exists in insoluble forms that makes its usability difficult. Some organisms secrete siderophores, low molecular weight compounds, that can chelate iron and convert it into usable forms for cells. One such organism, Rhizobium leguminosarum, is a nitrogen fixing symbiont proteobacteria that infects leguminous plants. The genome of Rhizobium leguminosarum ATCC 14479, which infects the red clover, Trifoli pratense, has previously been completely sequenced in our lab. Our lab has identified several genes in this strain involved in the biosynthesis of a siderophore, vicibactin. The protein product of one of …

The Impact Of Oxygen Availability And Oxidative Stress On Regulation Of Cyclic-Dimeric-Gmp In Listeria Monocytogenes Strain F2365, Anna G. Welch

Honors Theses

Listeria monocytogenes is a gram-positive foodborne pathogen that results in the infectious disease listeriosis. The second messenger molecule cyclic-dimeric-GMP has been found to be responsible for the regulation of expression of many of its virulence factors with diguanylate cyclases and phosphodiesterases regulating the intracellular concentration of cyclic-di-GMP through synthesis and degradation, respectively. This study investigated the possibility that the availability of oxygen is the environmental signal crucial to the regulation of these enzymes. Prior research in our laboratory has demonstrated that the intracellular concentration of cyclic-di-GMP is elevated when exposed to anaerobic conditions. Due to this, it was hypothesized that …

Study Of The Role Of The Msaabcr Operon In Tricarboxylic Acid Cycle Activity And Persister Cell Formation In Staphylococcus Aureus, Karsen Motter

Honors Theses

Staphylococcus aureus is an important human pathogen that causes wide arrays of infections ranging from minor skin infections to lethal systemic conditions such as infective endocarditis, osteomyelitis, sepsis and pneumonia. These systemic diseases are often difficult to treat due to the presence of persister cells. Persister cells are a phenotypic variant of the bacterial population that exhibit extreme and transient antibiotic tolerance accompanied by a transient halt in growth. Upon cessation of antibiotic treatment, however, persisters resume growth which results in recurrence of infections. This characteristic of persister cells therefore displays high clinical significance. In this study, we show the …

Interregulation Between Msaabcr Operon And Ccpe To Determine Staphylococcal Metabolism And Virulence, Erin R. Cox

Honors Theses

Staphylococcus aureus is a complex human pathogen that causes problems in both healthcare and community settings. Staphylococcus aureus is a gram-positive, sphere shaped bacterium that usually colonizes in the nasal cavity of healthy individuals. Staphylococcus aureus infections are a growing health concern due to its ability to produce virulence factors, such as pigmentation, protease production, and capsule formation. Two regulators in S. aureus virulence factors are msaABCR, which is a newly characterized operon, and ccpE. In order to determine the interaction between these two regulators in regulating virulence and metabolism in S. aureus, ccpE and ccpE/ …

Phosphodiesterase D Is Involved In Bile Resistance In Listeria Monocytogenes, Sophia A. Ali

Honors Theses

Listeria monocytogenes is a deadly foodborne bacterium that is responsible for almost 20% of food-related deaths in the United States. Listeria monocytogenes contaminates ready-to-eat products such as cheese, deli meat, and ice cream. Once ingested, it invades the intestinal lining and can enter the bloodstream, causing listeriosis. There is a gap in the knowledge of the pathogenesis of L. monocytogenes in how it is able to survive in the gastrointestinal tract in the presence of bile, which has bactericidal properties. Previous studies have suggested that the second messenger cyclic-dimeric-GMP may be involved in the regulation of virulence factors of Listeria. …

Phenotypic Characterizations Of Msaabcr Operon Deletion In Staphylococcus Epidermidis Rp62a, Raelyn Williams

Honors Theses

Staphylococcus epidermidis is a human pathogen that is increasingly known for its role in hospital infections associated with implantable medical devices. Antibiotic resistance has become a concerning issue for these infections as this bacteria have various virulence traits that help to evade immune response and antibiotic treatment. Currently, the most effective way to treat S. epidermidis infection is removal of the implant and long-term antibiotic treatment. S. epidermidis causes infection by expressing several protein factors that induce biofilm formation, the bacteria’s primary virulence mechanism. The purpose of this study was to perform the phenotypic characterizations of the msaABCR operon in …

The Role Of Gac/Rsm Signal Transduction Pathway In The Biology Of Antagonistic Marine Bacterium Gynuella Sunshinyii 449, Anhthu Truong

Honors Theses

Gynuella sunshinyii is a newly characterized bacterium with a remarkable ability to produce multiple secondary metabolites that act as potential antibiotics for medical applications. Currently, little is known about gene regulation in this unusual microorganism. In 2018, studies conducted of rhizosphere microbiomes of tidal marsh grasses on Deer Island, MS, resulted in multiple isolates of halophilic, aerobic, Gram-negative bacteria with antagonistic properties. One of the most active antagonists was identified as Gynuella sunshinyii 449. The genome of strain 449 was sequenced with Illumina MiSeq, assembled with Unicycler and SPAdes, and annotated with RASTtk. The annotation revealed a 6.09 Mb genome …