Microbiology Commons^™

An Overview Of The Extracurricular Polysaccaride Production Of Probiotic Lactic Acid Bacteria, Olujimi Babajide Olowokere

Theses (2016-Present)

The study focuses on a comprehensive review of lactic acid bacteria and their production of extracellular polysaccharide substrates (EPS). Two important factors are addressed in the work; and these are 1) identification of LAB stains found in the commercially sold daily milk, 2) significant factors impacting polysaccharide production. Motivation behind these focus points is to allow further inquiries and studies on exploring these strains of bacteria for human wellness promotion. With microbial EPS production being a recent interest of study among healthcare and food industries sectors, new species of bacteria are extensively exploited for further investigation to improve human health, …

Sorption Of Cellulases In Biofilm Enhances Cellulose Degradation By Bacillus Subtilis, Yijie Deng, Shiao Y. Wang

Faculty Publications

Biofilm commonly forms on the surfaces of cellulosic biomass but its roles in cellulose degradation remain largely unexplored. We used Bacillus subtilis to study possible mechanisms and the contributions of two major biofilm components, extracellular polysaccharides (EPS) and TasA protein, to submerged biofilm formation on cellulose and its degradation. We found that biofilm produced by B. subtilis is able to absorb exogenous cellulase added to the culture medium and also retain self-produced cellulase within the biofilm matrix. The bacteria that produced more biofilm degraded more cellulose compared to strains that produced less biofilm. Knockout strains that lacked both EPS and …

College Of Natural Sciences Newsletter, July & August 2022, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Volume 3, Issue 5

Page 1 Dean's Message
Page 2 Awards & Recognition
Page 3 Resources for Student Success
Page 4 Welcome to New Faculty & Staff
Page 5 Summer Activities in CNS
Page 9 Celebrating the lives of those who touched the College
Page 10 Media Coverage of CNS
Page 12 Open PRAIRIE Data
Page 13 Snaps from he start of the semester
Page 14 Science as Art Competition

Characterization Of Genetic Pathways Involved In Resistance To A Novel Antifungal Peptide, Kayla L. Haberman

Graduate Theses and Dissertations

Antibiotic resistance is increasing prevalence, particularly in Candida glabrata. This opportunistic pathogen is closely phylogenetically related to Saccharomyces cerevisiae; however, its characterization is limited. C. glabrata is only second to Candida albicans as a fungal pathogen in immunocompromised patients. Commonly resistant to azoles, the most common fungal therapy, it has become costly and challenging to treat. A histatin 5 derived antifungal peptide, KM29, has a high degree of efficacy in Candida species and S. cerevisiae. The objective of this work is to advance our understanding of the mechanism of action of KM29 against C. glabrata. Previous work in the lab …

Analyzing Staphylococcal Contamination On Surfaces And Bedside Areas Of A Neonatal Intensive Care Unit Of A Children's Hospital, Daniel See

Honors Theses

Staphylococci species are known to be a cause of Healthcare-Associated Infections (HAIs) in neonatal intensive care units (NICU). There is limited research about the surveillance and identification of staphylococci bacteria from NICUs. Surveillance of bacteria within the NICU helps to identify areas acting as reservoirs for bacteria so that new cleaning policies and techniques can be put in place to stop the spread of HAIs. The objective of this study was to swab sample sites in a local level IV hospital NICU and identify locations of staphylococci presence throughout the NICU. Forty-one swabs were selected from over 900 swabs collected …

Bacterial Chondronecrosis With Osteomyelitis In Broilers: Genomics, Phylogenomics, And Methods To Detect Specific Pathogens During Outbreaks., Abdulkarim Abdulaziz A. Shwani

Graduate Theses and Dissertations

Lameness is a major issue in animal welfare and the broiler industry. Bacterial chondronecrosis with osteomyelitis (BCO) is one of the main causes of lameness. Many staphylococcal species, including Staphylococcus agnetis isolate 908, have been isolated from the bones and blood of lame broilers at the University of Arkansas. Staphylococcus agnetis is a coagulase-variable, Gram-positive bacterial species that has been previously associated with subclinical or mild clinical cases of mastitis in dairy cattle. The annotated complete genome of hypervirulent strain 908 was published at NCBI. In this study, it has been compared to nine genomes we assembled for hypervirulent isolates …

Investigating The Role Of The Three N-Terminal Hamp Domains Of The Aer2 Chemoreceptor From Pseudomonas Aeruginosa, Selina Anaya

Loma Linda University Electronic Theses, Dissertations & Projects

Pseudomonas aeruginosa is a ubiquitous environmental bacterium and opportunistic human pathogen. It readily adapts to changing environmental conditions with the aid of 26 chemoreceptors that signal to four distinct chemosensory systems. The Aer2 chemoreceptor from P. aeruginosa is an O2 sensor implicated in stress responses, virulence and fine-tuning the chemotaxis (Che) system. Aer2 is the sole chemoreceptor of the Che2 chemosensory system, which forms complexes at the cell pole during stationary phase. Aer2 is soluble, yet membrane-associated and displays an unusual arrangement with its PAS sensing domain sandwiched between three N-terminal and two C-terminal HAMP domains. HAMP domains are widespread …

Microbial, Chemical, And Functional Components In Kefir, Natto, And Feed Ingredients, Dana Mccurdy

All Dissertations

Kefir grains were purchased from online, home kitchen vendors in the United States (n = 22), inoculated into UHT milk, and incubated at 25°C for 22 hours. Results indicated lactobacilli, lactococci and yeast in all samples. Six out of 11 samples contained coliform, and all samples contained pseudomonal and staphylococcal species. Using targeted genome sequencing (16S) of kefir grain samples 1, 2, and 3 revealed that lactobacilli were the predominant genera of bacteria. ITS sequencing revealed different fungal species in each grain. Results indicated potential presence of menaquinone-4 and menaquinone-7 by UPLC-MS/MS analysis.

The fermentation of whole and ground soybeans, …

Genomic Analysis And Characterization Of Surface Properties Of Naphthalene Degrading Acinetobacter Isolates, Gunn Emilie Berge

Graduate Theses and Dissertations (2019 - present)

No abstract provided.

A Cross-Scale Nexus: Microbial Functional Genes In Tandem With Molecular-Level Nitrogen Fluxes And Implications For Field-Scale Biogeochemical Processes, Srusti Maddala

Graduate Theses and Dissertations

Nitrogen (N) biogeochemical cycling entails close networking between soil nutrients, plant species and resulting microbial communities, and abiotic factors such as temperature, moisture, and pH. To better understand transformations of N in soil microsites, which are known to be rich in N-cycling behavior, the microdialysis technique was employed to generate in situ data on temporal alterations of N during wetting-drying conditions in both the field and laboratory. The objectives were to 1) determine the lifespan of the microdialysis technique in field conditions, 2) evaluate the ability of the method to yield N fluxes that would be differential between the two …

Defining The Importance Of The Hnrnp I Interaction To The Sindbis Virus Subgenomic Viral Rna Using An Innovative Tethering Approach., Claire Westcott

Electronic Theses and Dissertations

Old World alphaviruses cause significant outbreaks of illness and debilitating multi-joint arthritis for prolonged periods. Currently, there are no FDA approved vaccines or antiviral therapies; and thus, there is a critical need to identify and characterize the molecular biology of alphaviruses. Alphaviruses rely on the host cell machinery to complete the viral lifecycle and are dependent on interactions with host RNA binding proteins. Accordingly, several host heterogenous nuclear ribonucleoprotein proteins (hnRNPs) have been found to bind to the Sindbis virus (SINV) RNAs. Disrupting the interaction sites in the viral RNAs of these RNA:Protein interactions results in decreased viral titers in …

Habitability, And Evolution Of Microorganisms Under Extreme Conditions, Azarin Yazdani

Graduate Theses and Dissertations

The choice of a solvent determines the possible biochemistry of life. Life on Earth is based on carbon biochemistry and has evolved in an environment with water as a solvent. As a polar solvent abundant on Earth, water has unique physical properties, including a large range of liquidity and low viscosity, making it a very good solvent for terrestrial life. Liquids other than water are abundant in the universe, and the chemical nature of these liquids might lead to different chemistries of life. In the first chapter, we review the main characteristics of a good solvent, and then we use …

Allelopathic Effect Of Cereal Straw Extracts On Growth Of Raphidocelis Subcapitata And Microcystis Aeruginosa, Holly Wren

Graduate Theses and Dissertations

Harmful algal blooms are increasing in size, duration, and intensity around the globe. For several decades, cereal straws have been recognized as a viable algal control method, though the mechanisms by which cereal straws inhibit algae remain a topic of research. The objectives of this study were to evaluate the effectiveness of decomposing cereal straw extract, particularly rice (Oryza sativa) and barley (Hordeum vulgare) straw extract, to inhibit the green alga Raphidocelis subcapitata or cyanobacteria Microcystis aeruginosa in bioassays and to determine if the effectiveness of decomposing rice straw extract is altered by the presence of natural organic matter or …

Chondronecrosis With Osteomyelitis In Broilers: Bacterial Species Involvement And Influence Of Probiotics And Synbiotics, Amer Abdullah Hasan

Graduate Theses and Dissertations

Since 1945, the market for broiler production has evolved from a collection of smallholder poultry farms into an industry worth billions of dollars. Poultry production has not gone without challenges. Lameness in young broilers is presently a serious issue in the poultry industry for reasons of animal health and welfare, as well as significant lost production and revenue. Bacterial chondronecrosis with osteomyelitis (BCO) is a major form of lameness in broilers. This dissertation contains information about (i) the influence of Staphylococcus agnetis, Staphylococcus saprophyticus, Staphylococcus epidermidis and Enterococcus faecalis on inducing BCO lameness, (ii) evaluation of of probiotics for reducing …

Clostridioides Difficile Biofilm And Spore Production In Response To Antibiotics And Immune Stress, Adenrele M. Oludiran

Chemistry & Biochemistry Theses & Dissertations

The development of new therapeutic options against Clostridioides difficile (C. difficile) infection is a critical public health concern, as the causative bacterium is highly resistant to multiple classes of antibiotics. C. difficile, an anaerobic spore-forming Gram-positive pathogenic bacterium, is a major cause of hospital-acquired infections. C. difficile persists in the environment and spreads the infection to new hosts in the form of dormant spores and can persist within hosts as surface-attached biofilms. These studies investigate bacterial vegetative cell survival, biofilm formation, and sporulation in response to stress. Antimicrobial host-defense peptides (HDPs) are highly effective at simultaneously modulating …

Cyclic Di-Gmp Regulates Motility, Biofilm Formation, And Desiccation Tolerance In Acinetobacter Baumannii, Garrett Reynolds

Electronic Theses and Dissertations

Acinetobacter baumannii is an increasingly multidrug-resistant pathogen contributing to hospital-acquired infections necessitating the discovery of novel treatments. A bacterial second messenger, cyclic diguanosine monophosphate (cyclic di-GMP), can regulate various persistence factors that are potentially advantageous for survival in hospital environments. Cyclic di-GMP–modulating enzymes and cyclic di-GMP–binding effectors predictively are encoded in the Acinetobacter baumannii genome. I hypothesized that cyclic di-GMP controls motility, biofilm formation, and desiccation tolerance in Acinetobacter baumannii. Disrupting cyclic di-GMP–modulating enzymes or cyclic di-GMP–binding effectors should alter the regulatory effectiveness of these phenotypes. I tested the multidrug-resistant isolate Acinetobacter baumannii strain AB5075 and identified several transposon …

Identification Of Microorganisms From The Depths Of Wind Cave, Abbie Bangs, Justin Peters Ph.D., Joshua Sebree Ph.D.

Summer Undergraduate Research Program (SURP) Symposium

During 2022, samples were collected at Wind Cave National Park on three different trips. As the team goes deeper and deeper into the cave, the goal is to actively trace the types of microorganisms (fungi, bacteria, and archaea) throughout the cave. The process to obtain species level identification of these samples utilizes PCR amplification of different sections of their genomic DNA followed by sequencing analysis. An initial phylogenetic tree showing relatedness of the identified microorganisms is presented.

Exploring Microbes At Wind Cave As An Analog For Exobiological Environments Off Earth, Abby K. Sliwiniski, Emma W. Pellegrino, Nicole Geerdes, Marek K. Sliwinski

Summer Undergraduate Research Program (SURP) Symposium

Subterranean environments on Earth serve as an analog for the study of microbes on other planets. This has become an active area of research with the discovery of exoplanets. To learn about the microbial species living in Wind Cave, we are comparing methods to sample environmental DNA because most microbes cannot be cultivated using standard laboratory methods. We are then probing the environmental DNA with broad primers that are designed to amplify most life and narrower primers such as those specific to the domain Archaea. Of the methods compared, the Qiagen DNeasy Powerbiofilm kit produced the purest template as measured …

Arsr Family Regulator Msmeg_6762 Mediates The Programmed Cell Death By Regulating The Expression Of Hnh Nuclease In Mycobacteria, Xiangke Duan, Xue Huang, Junqi Xu, Xue Li, Jingjing Niu, Xiaoli Du, Xiaoyu Wang, Jiang Li, Michael Kelly, Jiaohan Guo, Ke Zhang, Yu Huang, Biao Kan, Jianping Xie

Biology Student Work

Programmed cell death (PCD) is the result of an intracellular program and is accomplished by a regulated process in both prokaryotic and eukaryotic organisms. Here, we report a programed cell death process in Mycobacterium smegmatis, an Actinobacteria species which involves a transcription factor and a DNase of the HNH family. We found that over-expression of an ArsR family member of the transcription factor, MSMEG_6762, leads to cell death. Transcriptome analysis revealed an increase in the genes’ transcripts involved in DNA repair and homologous recombination, and in three members of HNH family DNases. Knockout of one of the DNase genes, MSMEG_1275, …

Growth Outcomes Of Pseudomonas Aeruginosa Inhibitor Of Vertebrate Lysozyme Knockouts In Conditions Mimicking The Cystic Fibrosis Lung Environment, Amani Gaddy

Master of Science in Chemical Sciences Theses

Pseudomonas aeruginosa (PA) is a Gram-negative bacterium, often found in cystic fibrosis (CF) patients and can lead to the decline of lung functioning and premature death in 80% of infected patients when microcolonies form within the mucin of the lung. Due to its major capacity for antibiotic resistance, an alternative strategy towards defending against the bacterial invasion of PA is by the antibacterial activity of our own innate immune system with use of elements such as lysozyme. Pseudomonas aeruginosa inhibitor of vertebrate lysozyme class 1 (Ivyp1) is a periplasmic protein produced by gram-negative bacteria that inhibits the enzymatic activity of …