Pseudomonas Aeruginosa Evades Predation By Myxococcus Xanthus, Sarah Joie Beauvais

Symposium of Student Scholars

Multidrug-resistant Pseudomonas aeruginosa causes an estimated 32,600 hospital-acquired-infections and 2,700 estimated deaths in the US in 2017(CDC). Myxococcus xanthus is a strain of myxobacteria that preys on Pseudomonas sp, through the production of antibiotics and digestive enzymes. In previous experiments, P. aeruginosa evaded predation, through an unknown mechanism. Using confocal microscopy, this research investigates if quorum sensing, a cell density-dependent signaling pathway, could be a factor in motility and evasion of M. xanthus. Liquid suspensions of log-phase PA01 were dyed with two fluorescent dyes: SYTO 9 for marking live cells and Propidium iodide (PI) for marking dead cells. …

Microbial Diversity And Community Structure In Sediments Associated With The Seagrass (Thallassia Testudinum) In Apalachicola Bay, Florida, Rahma Ahmed, Thomas Mcelroy, Troy Mutchler

Symposium of Student Scholars

Seagrass is an angiosperm which provides many ecosystem services in coastal areas, such as providing food, shelter and nurseries for many species, and decreasing the impact of waves on shorelines. A global assessment reported that 29% of known seagrass meadows are in a state of decline due to the effects of human activity. Seagrass is commonly found in shallow marine waters where they form meadows containing a microbiome that plays an important role in providing nutrients for seagrass growth, though little is known about the microorganisms within the seagrass meadow sediments. Our project collected sediments from seagrass meadows and adjacent …

Analysis And Identification Of Lipolytic Bacterial Species For The Degradation Of Wastewater Lipids, Lindsay C. Smoak

Honors College Theses

The aim of this study was to isolate native bacterial strains from the wastewater treatment facilities of Statesboro, GA to identify their lipolytic activities. Obtained bacterial strains were further assessed via morphological and biochemical methods to determine their enzymatic capabilities. Use of the detergent Tween-20 in growth mediums was the first criteria to assess lipase activity, and these isolates were further investigated to quantitatively measure lipase presence and activity. Lipase protein was precipitated and dialyzed to perform a lipase activity assay, followed by Sodium Dodecyl Sulphate–Polyacrylamide Gel Electrophoresis (SDS-PAGE) to confirm the presence of the lipolytic enzymes. Sanger sequencing was …

Investigating Alternative Induction Of The S. Aureus 80a Prophage, Jody Caretti

Student Scholar Showcase

Widespread antibiotic resistance has quickly become one of the most concerning crises affecting modern medicine, especially in cases of Staphylococcal infections, which have become resistant to all ��-lactam antibiotics. As a result, research into alternative forms of treatment for bacterial infections is a top priority. Bacteriophage therapy is a popular candidate for replacing antibiotics, due to the way the viruses interact with the bacteria. The 80�� prophage integrates its DNA into Staphylococcus aureus strain 10616 via the lysogenic cycle, and replicates with the bacterial cell. When stressed, the bacteria stop replicating and the prophage stimulates the lytic cycle, activating transcription …

Sars-Cov-2 Reveals That Chimeric Agents Are The Bioweapons Of The Future, Rachel Craig

Senior Honors Theses

Bioweapons programs have existed since their development during the Cold War. These biowarfare programs initially utilized naturally occurring pathogens capable of infecting crops, livestock populations, and human populations. Anthrax is a widely exploited bioagent responsible for attacks ranging from the Germans’ deployment in World War I to the mailing of anthrax through the postal service in attempts on U.S. senators’ lives. With the development of genetic manipulations, the Soviet Union began modifying anthrax to resist detection and treatment. With the continued advancement of science and technology, a new bioagent has entered the scene – the man-made chimeric virus. Chimeric viruses …

Characterization Of A Medium-Dependent Streptomyces Developmental Mutant, Dylan Gray, Jennifer A. Bennett

Undergraduate Distinction Papers

Streptomyces coelicolor is a soil-dwelling, Gram-positive Actinobacteria. Streptomyces species produce thousands of secondary metabolites which include many antibiotics used in medicine today. In Streptomyces development, as colonies grow, secondary metabolites are produced, and ultimately mature spores are dispersed. The production of each of these secondary metabolites in wild-type Streptomyces is determined by a distinct biosynthetic pathway. In order to identify new genes for antibiotic production and other aspects of development, an engineered Tn5-derived transposon was used to mutagenize wild-type cells in vivo and produce single, stable insertions.

Colonies that were visually distinct from the wild type were selected for further …

Isolation And Identification Of Bacillus Spp. From Syrian Soils And Testing Their Antifungal Activity Against Botrytis Cinerea In Vitro (In Vitro) في ظروف المخبر (Botrytis Cinerea)من ترب سورية واختبار فعاليتها التضادية تجاه الفطر (Bacillus) عزل وتعريف أنواع من الجنس, Naffaa Walid

Arab Journal of Arid Environments المجلة العربية للبيئات الجافة

Three hundred seventy eight isolates of Bacillus spp. from Syrian soils were screened in vitro for their ability to inhibit the growth of Botrytis cinerea, agent of gray mold disease. The B307 isolate showed the highest antagonism activity with growth inhibition of 68%. In addition, B307 had chitinolytic activity, and the fraction from the isolate with more than 50KDa of its cell free crude extract showed the highest chitinolytic and antagonism activity against B. cinerea. This isolate was identified as Bacillus licheniformis according to the 16S DNA gene sequencing data with homology of 99%. The results of this …

Antibacterial, Hemagglutination, And Insecticidal Activity Studies On The Solvent Extracts Of The Roots Of Olea Ferruginea, Muhammad Yaseen, Muhammad Kamran, Arshad Farid, Salmah Ismail, Muhammad Muzammal, Kamal Abdul Amir, Muhammad Hashim Khan, Sohail Ahmad, Sheikh Abdur Rashid

Makara Journal of Science

Olea ferruginea has been used to treat skin ailments, as well as kidney and ocular problems for a long time. The current study was designed with the aim of investigating and scientifically validating its widespread use. Chloroform, n-hexane, and ethyl acetate were used to assess the antibacterial, hemagglutination, and insecticidal properties of O. ferruginea roots. Escherichia coli, Micrococcus luteus, Klebsiella pneumoniae, and Pseudomonas aeruginosa were among the bacterial strains selected for assessing antibacterial activity. The results showed that ethyl-acetate (EtOAc) extract (56%) and chloroform (CHCl₃) extract (56%) showed the widest zone of inhibition against …

Ohio Anuran Gut Microbiomes, Serena Hoffman

Undergraduate Honors Thesis Projects

Recent studies focusing on the skin and gut microbiome of vertebrates have found how important microbiomes are to maintaining host health. Understanding the role the gut microbiome plays to host health is of great importance for conservation. Less is known about the gut microbiome than the skin microbiome for amphibians. Literature is especially lacking for local Ohio anuran species. The purpose of this study was to establish the baseline composition of the gut microbiome for local Ohio anurans and to determine whether host species or habitat is the best predictor of gut microbiome composition. Tadpoles were collected from seven different …

The Role Of Cd5 In The Periodontal Disease: Insights Into Chronic Inflammation, Ellie Bybee

Annual Research Symposium

No abstract provided.

Antibacterial Activity, Structure-Activity Relationships, And Scale-Up Reaction Of 1,3,4-Oxadiazoles, Olivia Marie Smith

Undergraduate Honors Thesis Projects

Oxadiazoles are compounds in the field of organic chemistry that have been gathering interest in the medicinal chemistry and microbiology communities for their biological properties, which range from anti-inflammatory agents, to chemotherapy drugs, to antibiotics. The synthesis of oxadiazoles can be difficult due to the expensive and complex nature of the techniques used as well as the volatile reagents and elevated temperatures that are often required in organic synthesis. The Grote lab has recently developed a new method for the synthesis of 1,3,4-oxadiazoles under mild conditions. The goals of this thesis were thus twofold: to develop a viable scale-up procedure …

Combination Of Amphiphilic Cyclic Peptide [R4W4] And Levofloxacin Against Multidrug-Resistant Bacteria, Muhammad Imran Sajid, Sandeep Lohan, Shun Kato, Rakesh Kumar Tiwari

Pharmacy Faculty Articles and Research

Bacterial resistance is a growing global concern necessitating the discovery and development of antibiotics effective against the drug-resistant bacterial strain. Previously, we reported a cyclic antimicrobial peptide [R₄W₄] containing arginine (R) and tryptophan (W) with a MIC of 2.67 µg/mL (1.95 µM) against methicillin-resistant Staphylococcus aureus (MRSA). Herein, we investigated the cyclic peptides [R₄W₄] or linear (R₄W₄) and their conjugates (covalent or noncovalent) with levofloxacin (Levo) with the intent to improve their potency to target drug-resistant bacteria. The physical mixture of the Levo with the cyclic [R_{4 …}

Characterization Of Streptomyces Nymphaeiformis Sp. Nov., And Its Taxonomic Relatedness To Other Polyhydroxybutyrate-Degrading Streptomycetes, Gary R. Hix, Muhammad S. Khan, Mikayla T. Miller, Elisha C. Napier, Allison L. O'Brien, Roger P. White, Stephen F. Baron Ph.D.

Biology Faculty Scholarship

A polyhydroxybutyrate (PHB)-degrading actinomycete, strain SFB5A^T, was identified as a species of Streptomyces based on its membrane fatty acid profile and the presence of LL-diaminopimelic acid in the cell wall. It formed sporulating mycelia on most agar media, but flat or wrinkled, moist colonies on trypticase soy agar. Spores were smooth, cylindrical, and borne on long, straight to flexuous chains. It produced a light brown diffusible pigment, but not melanin. Comparison of genomic digital DNA–DNA hybridization (dDDH) and average nucleotide identity (ANI) values indicated that strain SFB5A^T was related to Streptomyces litmocidini JCM 4394^T , Streptomyces …

Escherichia Coli Alanyl-Trna Synthetase Maintains Proofreading Activity And Translational Accuracy Under Oxidative Stress, Arundhati Kavoor, Paul Kelly, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Aminoacyl-tRNA synthetases (aaRSs) are enzymes that synthesize aminoacyl-tRNAs to facilitate translation of the genetic code. Quality control by aaRS proofreading and other mechanisms maintains translational accuracy, which promotes cellular viability. Systematic disruption of proofreading, as recently demonstrated for alanyl-tRNA synthetase (AlaRS), leads to dysregulation of the proteome and reduced viability. Recent studies showed that environmental challenges such as exposure to reactive oxygen species can also alter aaRS synthetic and proofreading functions, prompting us to investigate if oxidation might positively or negatively affect AlaRS activity. We found that while oxidation leads to modification of several residues in Escherichia coli AlaRS, unlike …

The Coxsackievirus And Adenovirus Receptor Has A Short Half-Life In Epithelial Cells, Poornima Kotha Lakshmi Narayan, James M. Readler, Mahmoud S. Alghamri, Trisha L. Brockman, Ray Yan, Priyanka Sharma, Vladislav Snitsarev, Katherine J.D.A Excoffon, Abimbola O. Kolawole

Department of Biology Faculty Scholarship and Creative Works

The coxsackievirus and adenovirus receptor (CAR) is an essential cellular protein that is involved in cell adhesion, cell signaling, and viral infection. The 8-exon encoded isoform (CAREx8) resides at the apical surface of polarized epithelia, where it is accessible as a receptor for adenovirus entering the airway lumen. Given its pivotal role in viral infection, it is a target for antiviral strategies. To understand the regulation of CAREx8 and determine the feasibility of receptor down regulation, the half-life of total and apical localized CAREx8 was determined and correlated with adenovirus transduction. Total and apical CAREx8 has a relatively short half-life …

Characterizing The Amino Acid Activation Center Of The Naturally Editing-Deficient Aminoacyl-Trna Synthetase Phers In Mycoplasma Mobile, Nien-Ching Han, Arundhati Kavoor, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

To ensure correct amino acids are incorporated during protein synthesis, aminoacyl-tRNA synthetases (aaRSs) employ proofreading mechanisms collectively referred to as editing. Although editing is important for viability, editing-deficient aaRSs have been identified in host-dependent organisms. In Mycoplasma mobile, editing-deficient PheRS and LeuRS have been identified. We characterized the amino acid activation site of MmPheRS and identified a previously unknown hyperaccurate mutation, L287F. Additionally, we report that m-Tyr, an oxidation byproduct of Phe which is toxic to editing-deficient cells, is poorly discriminated by MmPheRS activation and is not subjected to editing. Furthermore, expressing MmPheRS and the hyperaccurate variants renders …

Clostridioides Difficile Motility In Defined Culture Media And Its Response To Nutrients, Mary Ishak

Honors Undergraduate Theses

In recent years, Clostridiodes difficile has caused a sharp increase in hospital-acquired infections. Patients on multiple courses of antibiotics experience a general clearing of normal gut microbiota, leading to dysbiosis and an opportunity for C. difficile to colonize the colon. Understanding which nutrients produce optimal respiratory metabolism in C. difficile will help to determine the reasoning behind whether the microbe invests its energy into various cellular processes, such as motility. Different C. difficile strains were first cultured in BHIS broth (brain-heart infusion, supplemented) and CDMM broth (C. difficile minimal media) before being used to inoculate soft agar wells. The …

Isolation And Characterization Of Novel B. Subtilis Bacteriophages, Johnson Phung, Rebecca Adams

Science University Research Symposium (SURS)

Bacteriophages are viruses that infect bacteria cells. Bacteria, being the most abundant form of life on the planet, have an estimated ten to a hundred different types of bacteriophages that infect each species. Bacteriophages are everywhere on Earth, but the number of phages that have been identified is only a fraction of what are thought to exist. This project focuses on isolating and identifying phages that infect the bacterium Bacillus subtilis. B subtilis is a decomposition microbe commonly found in the soil. Our first goal was to determine whether the 3 samples of Bacillus subtilis phages that were previously …

An Optimal Lysis Time Maximizes Bacteriophage Fitness In Quasi-Continuous Culture, Sherin Kannoly, Abhyudai Singh, John J. Dennehy

Publications and Research

Optimality models have a checkered history in evolutionary biology. While optimality models have been successful in providing valuable insight into the evolution of a wide variety of biological traits, a common objection is that optimality models are overly simplistic and ignore organismal genetics. We revisit evolutionary optimization in the context of a major bacteriophage life history trait, lysis time. Lysis time refers to the period spanning phage infection of a host cell and its lysis, whereupon phage progenies are released. Lysis time, therefore, directly determines phage fecundity assuming progeny assembly does not exhaust host resources prior to lysis. Noting that …

Computational Strain Analysis In Microbiome Datasets With Application To Skin Disease, Minerva Fatimae Ventolero

Electronic Theses and Dissertations, 2020-2023

Identifying bacterial strains is important not only for human health research but also for various environmental and industrial applications. The plethora of available shotgun metagenomic datasets provide an unprecedented opportunity to discover novel bacterial strains in different environmental niches. In this thesis, we evaluated the existing novel-strain-based tools and showed that their performance is still suboptimal. Due to the difficulty in distinguishing strains of similar abundance by available tools, the SMS (strains in multiple samples) tool was developed to de novo identify bacterial strains in multiple shotgun metagenomic samples. We showed that SMS distinguishes strains of similar abundance well and …