Microbiology Commons^™

Mapping The Effects Of 5’ Untranslated Region Deletions On Translation Of 3a In Bmv Rna3, Courtney Marie Bozman

Graduate Research Theses & Dissertations

Brome mosaic virus (BMV) is a positive sense, single-stranded RNA virus that infects a wide array of plant hosts globally including: wheat, oats, maize, barley, and rye. Since its discovery in the 1940s, BMV has served as a model organism in uncovering the modalities of viral infectivity, composition, translation, and replication. In many viruses, it is typically imperative to recruit cellular machinery to produce viral proteins as their coding capacity is limited. Therefore, there are sequences and structures within the leader sequences allow them to be competitive with the eukaryotic mRNAs. Although BMV has been thoroughly researched in these other …

Modeling Disease Impact Of Vibrio-Phage Interactions, Christopher Botelho

Electronic Theses and Dissertations

Since the work of John Snow, scientists and medical professionals have understood that individuals develop cholera by means of consuming contaminated water. Despite the knowledge of cholera's route of infection, many countries have experienced and still experience endemic cholera. Cholera is caused by the Vibrio cholerae (V. cholerae) bacterium and presents with acute diarrhea and vomiting. If untreated, infected individuals may die due to dehydration. Cholera is a disease that most commonly affects countries with poor infrastructure and water sanitation. Despite efforts to control cholera in such countries, the disease persists. One such example is Haiti which has been experiencing …

Impact Of Industrial Biocides On Bacterial Isolates From Hydraulic Fracturing Produced Water, Waad Ahmed Aljohani

Dissertations, Master's Theses and Master's Reports

Biocides are antimicrobial compounds that are designed to kill diverse groups of microbes in an untargeted fashion. Glutaraldehyde and DBNPA are commonly used to manage microbial growth in different industries. It is possible that biocide use may result in the development of bacterial resistance. However, resistance to DBNPA is believed to be limited under normal use conditions. We isolated a number of bacteria from produced water from a hydraulically fractured site in West Texas. We then tested the ability of these isolates to resist Glutaraldehyde and DBNPA. In this study, we found that these isolates have varying resistance to these …

The Role Of Rmta In The Opportunistic Pathaogen Aspergillus Fumigatus, Roshan Dahal

Graduate Research Theses & Dissertations

The fungus Aspergillus fumigatus is an opportunistic human pathogen capable of causing

a life-threatening systemic lung infection known as invasive aspergillosis among immune compromised

patients. This group includes individuals infected with HIV, people with hematological

malignancies, solid organ transplant patients, persons with genetic immunodeficiency and cancer

patient undergoing chemotherapy. Due to the medical relevance of this organism, it is imperative

to discover novel genetic elements to design antifungal drugs against A. fumigatus dissemination,

virulence and survival during human infection. Previously, the putative arginine methyltransferase

gene rmtA was characterized in the model organism Aspergillus nidulans and the opportunistic

plant pathogen Aspergillus …

Practical Bioinformatics Applications In Microbes, Sarah Anne Entwistle

Graduate Research Theses & Dissertations

This thesis examines three methodologies for applying bioinformatics techniques to microbial data. A computational analysis of RNA sequencing data showed that hbx1 is a global regulator in Aspergillus flavus. A particular focus of this analysis is the characterization of hbx1 in regard to regulation of secondary metabolite gene clusters and their production of aflatoxins. An analysis of bacterial genomes identified ORFans in both pathogenic and non-pathogenic genomes, along with their presence in sequence features. This investigation demonstrated that ORFan genes shared by pathogenic genomes were more related to bacterial pathogenicity. Evaluation of multiple types of recombination events in RNA sequencing …

The Link Between Antibiotic Resistance Used For Recombinant Dna Selection And Cellular Phenotype In Rat Liver Epithelial Cells, Doaa Alshammari

Graduate Research Theses & Dissertations

Recombinant DNA plasmids are often used to mediate forced gene overexpression or suppression in mammalian cells, to address questions regarding the role of specific proteins in cell behavior and function. To select for cells harboring such recombinant plasmids, lethal antibiotics such as Puromycin, Geneticin (Neomycin) and Zeocin are frequently used, as plasmids contain selective antibiotic resistance genes that biochemically disarm them. Antibiotic resistance, induced by plasmid-borne genes and chronic exposure to lethal antibiotics can likewise potentially change the phenotype of cells, confounding the conclusions drawn from experiments on gene overexpression or suppression. Yet, little is known about the effects of …

Microbiome And Metagenome Of An Anthropogenic Hyperalkaline Slag-Fill Waterway In South Chicago, Illinois, Usa, Jan Ingemar Ohlsson

Graduate Research Theses & Dissertations

The aquifers and waterways around the Lake Calumet area of south Chicago, IL, USA have been affected by a century of intensive industrial waste dumping. Steel slag in particular was used as infilling to claim most of the Calumet Wetlands for industrial and residential development. Since the prohibition and cessation of these disposal activities, a growing body of research has recorded the environmental and health effects of the infill, particularly where interactions between slag minerals and rainwater produces extremely alkaline groundwater (pH ≥13). Atmospheric carbon dioxide interacting with these calcium hydroxide-rich slag fluids produces massive precipitation of a loose, white …

Detection Of Beta-Lactamase Variants In Municipal Wastewater And Fresh Water, Sunil Pandey

Masters Theses

The occurrence and spread of antibiotic-resistant genes (ARGs) are pressing public health problems worldwide. A key factor contributing to the spread of ARGs is lateral gene transfer. Wastewater treatment plants (WWTPs) are measured hot spots of microbial diversity and resistance because they receive polluted wastewater from diverse sources and contain a variety of different environments with dense bacterial loads. Due to the overuse of antibiotics the genetic capacities of microbes have profited. This helps every source of resistance gene and every means of horizontal gene transmission to develop the multiple mechanism of resistance to each antibiotic used clinically, agriculturally, or …

Study Of Genetic Regulators That Control Development And Secondary Metabolism In The Genus Aspergillus, Timothy Satterlee

Graduate Research Theses & Dissertations

In this study, I investigated the role of two different regulatory genes in two different species of pathogenic fungi from the genus Aspergillus. The first study involves a transcriptome analysis of the epigenetic regulator rmtA in the plant pathogen Aspergillus flavus. A. flavus colonizes numerous oil seed crops such as corn, peanuts, treenuts and cotton worldwide, contaminating them with aflatoxins and other harmful potent toxins. Previously our lab characterized the gene rmtA, which encodes an arginine methyltransferase in A. flavus, and demonstrated its role as regulator of the expression of the aflatoxin gene cluster and concomitant synthesis of toxin. Furthermore, …

Impacts Of Plant-Microbe Interactions On Seedling Performance In A Riparian Forest Invaded By Lonicera Maackii, Taylor E. K. Strehl

Masters Theses

Soil microbes have profound impacts on plant growth and survival and can either promote or inhibit plant dominance. Exotic plants are often strongly invasive because they have escaped their natural enemies, potentially including antagonistic soil microbes. I examined how the invasive shrub Lonicera maackii and a common native tree, Acer negundo, responded to soil microbial communities to determine the role of soil microbes in regulating invasion success. This was done by growing both species with microbes from invaded (L. maackii) and uninvaded (A. negundo) soils collected from three locations within a riparian forest. Seedlings were …

Evaluation Of Intra-Species Diversity Of Oxalobacter Formigenes Strains Using Pulsed-Field Gel Electrophoresis (Pfge) And Multiplex Pcr, Nivedita Pareek

Masters Theses

Oxalobacter formigenes is a beneficial, strict anaerobic gut bacterium that plays an important role in the prevention of kidney stone disease with a unique characteristic of using only oxalate as a carbon and energy source. To date, twenty-one strains of O. formigenes have been isolated which are further divided into two groups based on differences in the patterns of cell membrane lipids, cellular proteins, and nucleic acid fragments. The objective of the study was to evaluate intra-species diversity of O. formigenes strains using pulsed-field gel electrophoresis (PFGE) and multiplex PCR.

Nine pure cultures of O. formigenes strains (5 strains group …

Xylan Metabolism By Caulobacter Crescentus, Viet Bui

Masters Theses

Bacteria present unique opportunities to explore the molecular mechanisms of nutrient acquisition processes at single cell level under various experimental conditions. Caulobacter crescentus is a gram-negative oligotrophic environmental bacterium with adaptive physiological responses, such as slow growth or complete arrest of cell cycle, presence of sessile and motile progenies with the sessile cells growing stalk to enhance nutrient uptake for growth in low-nutrient conditions. Details of plant polysaccharide-derived carbon compound, such as cellobiose, maltose, and xylose utilization by C. crescentus can be found but molecular details or mechanisms of polysaccharide utilization, such as xylan, has not been reported. Database analyses …

Efficacy Of Cold Plasma For Direct Deposition Of Antibiotics As A Novel Approach For Localized Delivery And Retention Of Effect, Agatha Los, Dana Ziuzina, Daniela Boehm, Lu Han, Denis O'Sullivan, Liam O'Neill, Paula Bourke

Articles

Antimicrobial coating of medical devices has emerged as a potentially effective tool to prevent or ameliorate device-related infections. In this study the plasma deposition process for direct deposition of pharmaceutical drugs on to a range of surfaces and the retention of structure function relationship and antimicrobial efficacy against mono-species biofilms were investigated. Two selected sample antibiotics—ampicillin and gentamicin, were deposited onto two types of surfaces—polystyrene microtiter plates and stainless steel coupons. The antimicrobial efficacy of the antibiotic-coated surfaces was tested against challenge populations of both planktonic and sessile Escherichia coli and Pseudomonas aeruginosa, with responses monitored for up to …

Best Practices In Patellar Tendinopathy Management: An Evidence To Practice Review, Christopher J. Burcal, Adam B. Rosen, Tony Taylor, Mike Nicola

Clinical Practice in Athletic Training

Patellar tendinopathy (PT) is a degenerative condition that is common in sporting populations due to the loads placed on the tendon during dynamic activity. PT often occurs in overtraining situations; however, it may also occur in conjunction with and/or worsen through poor biomechanics, persistent inflammation, and altered movement patterns. Although sports medicine practitioners have evidence to support the prevalence of this injury, we do not have a strong base of evidence surrounding the contributing factors and pathophysiology that lead the pain and disability reported in patients with PT. The purpose of this evidence to practice review was to summarize a …

Mine Reclamation Using Biofuel Crops: Insights Into The Microbial Ecology Of The Switchgrass (Panicum Virgatum) Microbiome, Brianna L. Mayfield

Graduate Theses, Dissertations, and Problem Reports (ETD)

Bioenergy crop production has steadily increased due to growing political support for renewable energy, thus initiating a demand to find alternative agricultural land. An innovative option is the use of marginal soils, such as reclaimed mine lands, to produce bioenergy crops. Switchgrass (Panicum virgatum) is a promising bioenergy crop that can be grown on marginal lands due to its robust growth in various soil types and climates. However, little is known regarding plant-microbe interactions among switchgrass systems within reclaimed mine lands. A study conducted in 2008 grew switchgrass on high- and low- quality reclaimed mine sites (Hampshire and …

Cationic Biaryl 1,2,3-Triazolyl Peptidomimetic Amphiphiles: Synthesis, Antibacterial Evaluation And Preliminary Mechanism Of Action Studies, Andrew J. Tague, Papanin Putsathit, Katherine A. Hammer, Steven M. Wales, Daniel R. Knight, Thomas V. Riley, Paul A. Keller, Stephen G. Pyne

Research outputs 2014 to 2021

Synthetic small molecular antimicrobial peptidomimetics represent a promising new class of potential antibiotics due to their membrane-disrupting ability and their decreased propensity for bacterial resistance. A library of 43 mono- and di-cationic biaryl 1,2,3-triazolyl peptidomimetics was designed and synthesized based upon previously established lead biarylpeptidomimetics and a known pharmacophore. A reliable, facile and modular synthetic pathway allowed for the efficient synthesis of multiple unique scaffolds which were subjected to divergent derivatization to furnish the amphiphilic compounds. In vitro testing revealed enhanced antibacterial efficacy against a range of pathogenic bacteria, including bacterial isolates with methicillin, vancomycin, daptomycin, or multi-drug resistance. Preliminary …

Regulation Of Acetyl Phosphate-Dependent Acetylation And Identification Of Novel Lysine Acetyltransferases In Escherichia Coli, David George Christensen

Dissertations

Over billions of years, organisms have organized chemical reactions into metabolic pathways to sustain life. However, metabolic substrates can undergo many uncatalyzed, extra-metabolic reactions. Acetyl phosphate (AcP), an intermediate of the acetate fermentation pathway in E. coli, is one such metabolite that has been shown to non-enzymatically acetylate hundreds of proteins. This diverse set of targets suggests that acetylation could be a way for the cell to sense its nutritional status and regulate protein activity accordingly. However, how E. coli regulates acetylation, if at all, is unknown.Previous work showed that acetylation becomes pronounced in stationary phase cells. I determined that …

Membrane Microdomains As Platforms For Extra-Cellular Fusions, Michael Hantak

Dissertations

Life requires biological membranes. Membrane-enclosed compartments separate and unite through dynamic fission and fusion reactions. These are catalyzed processes that are central in organismal biogenesis. This dissertation focuses on extracellular membrane fusions, which are central to several processes. (1) Enveloped viruses enter cells through membrane fusions. (2) Extracellular vesicles (EVs) also deliver molecules into cells through membrane fusions. (3) Entire cells also fuse together, generating fertilized zygotes, skeletal muscles, and giant cell macrophages.Mechanisms of extracellular membrane fusion are poorly understood. This dissertation aimed to further define these mechanisms. We focused on regulatory cofactors, including tetraspanins, transmembrane proteins that cluster into …

Aerococcus Urinae: Establishing The Pathogenesis Of An Emerging Uropathogen, Evann E. Hilt

Dissertations

Urinary tract infection (UTI) is the world's most common bacterial infection. Much is known about the infectious process (pathogenesis) of a few of the bacteria that cause these infections, especially E. coli. Unfortunately, the pathogenesis of E. coli and other uropathogenic bacteria was explored almost exclusively in the belief that the bladder is supposed to be sterile. Our recent evidence, however, debunks this dogma. We used modern methods to reveal diverse bacterial communities in the bladders of adult women. These communities differ in women with and without lower urinary tract symptoms (LUTS), including UTI and urinary incontinence (UI). Many bacteria …

การตรึงยีสต์จากน้ำทะเลย่อยสลายดีเซลบนเปลือกหอยแครงและการประยุกต์, สุรสิทธิ์ พฤกษวานิช

Chulalongkorn University Theses and Dissertations (Chula ETD)

จุลินทรีย์สายพันธุ์ SP21 ที่คัดแยกได้จากน้ำทะเลปนเปื้อนน้ำมัน จากอำเภอดอนสัก จังหวัดสุราษฎร์ธานี ลักษณะทางสัณฐานวิทยาและการเปรียบเทียบลำดับนิวคลิโอไทด์ 26s rDNA พบว่าสายพันธุ์ SP21 มีความใกล้เคียงกับยีสต์ Candida viswanathii 100% C. viswanathii สายพันธุ์ SP21 สามารถย่อยสลาย 1% ดีเซล ในน้ำทะเลสังเคราะห์ (SSW) ได้ 96.18 ± 1.2% ใน 7 วัน ในขณะที่ชุดควบคุมที่ไม่เติมยีสต์ดีเซลลดลงเพียง 11.80 ± 6.13% เมื่อตรึง C. viswanathii สายพันธุ์ SP21 บนเปลือกหอยแครง พบว่าสามารถตรึงเซลล์ได้ 5.70 log CFU/กรัม เมื่อบ่มเซลล์ร่วมกับเปลือกหอย 1 ชั่วโมง และสามารถตรวจพบเซลล์ตรึงโดยกล้องจุลทรรศน์อิเล็กตรอนแบบส่องกราด เซลล์ตรึงสามารถย่อยสลาย 1% ดีเซล ในอาหารน้ำทะเลสังเคราะห์ (SSW) ได้ 98.70 ± 0.57% ในขณะที่ชุดทดลองเปลือกหอยแครงที่ไม่ตรึงเชื้อดีเซลลดลงเพียง 1.65 ± 7.34% การตรึงเซลล์ช่วยเพิ่มประสิทธิภาพการย่อยสลายดีเซลที่ความเข้มข้นสูง 3% และ 5% ได้ 94.06 ± 5.94% และ 86.50 ± 13.70% ในเวลา 7 วัน ตามลำดับ ในขณะที่เซลล์อิสระสามารถย่อยสลายได้เพียง 85.12 ± 1.67% และ 51.69 ± 1.79% เซลล์ตรึงยังสามารถย่อยสลาย 1% ดีเซล ในน้ำกร่อยสังเคราะห์ (SBW) และน้ำจืดสังเคราะห์ (CFMM) ได้ 93.21 ± 0.76% และ 90.25 ± 6.93% …

การต้านการเจริญและการผลิตสารพิษจากราของ Aspergillus Flavus และ Aspergillus Carbonarius โดยยีสต์ปฏิปักษ์, พิชามญชุ์ โสมา

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้มีวัตถุประสงค์เพื่อศึกษากลไกสำคัญในการยับยั้งการเจริญและการผลิตอะฟลาทอกซินบี 1 และโอคราทอกซินเอของ Aspergillus flavus และ Aspergillus carbonarius ตามลำดับ โดยใช้ยีสต์ปฏิปักษ์สามชนิด ได้แก่ Wickerhamomyces anomalus MSCU 0652, Saccharomyces cerevisiae MSCU 0654 และ Kluyveromyces marxianus MSCU 0655 จากผลการวิจัยพบว่า ยีสต์ปฏิปักษ์ทั้งสามชนิดสามารถยับยั้งการเจริญและการผลิตสารพิษจากราได้อย่างมีประสิทธิภาพแตกต่างกัน โดยมีกลไกสำคัญ ได้แก่ การสร้างสารประกอบอินทรีย์ระเหยง่ายที่มีผลต่อลักษณะทางสัณฐานวิทยาของเส้นใยรา และเมื่อศึกษาปัจจัยที่ส่งผลต่อการสร้างสารประกอบอินทรีย์เหยง่ายของยีสต์ปฏิปักษ์พบว่า W. anomalus MSCU 0652 มีประสิทธิภาพในการสร้างสารประกอบอินทรีย์ระเหยง่ายเพื่อยับยั้งการเจริญและการผลิตอะฟลาทอกซินบี 1 ของ A. flavus M3T8R4G3 ได้ดีที่สุดเมื่อเจริญบนอาหารที่ค่าความเป็นกรด-เบสเท่ากับ 5 (81.27±1.23 เปอร์เซ็นต์) บ่มที่อุณหภูมิห้อง (81.38±1.80 เปอร์เซ็นต์) และค่าความเข้มข้นของอาหารเลี้ยงยีสต์ปกติ (82.86±1.14 เปอร์เซ็นต์) และลดการผลิตอะฟลาทอกซินบี 1 ได้ดีที่สุดเมื่อเจริญบนอาหารที่ค่าความเป็นกรด-เบสเท่ากับ 4.5 (99.91±0.01 เปอร์เซ็นต์) บ่มที่ 25 องศาเซลเซียส (99.73±0.21 เปอร์เซ็นต์) และค่าความเข้มข้นของอาหารเลี้ยงยีสต์ 0.5 เท่า (99.67±0.12 เปอร์เซ็นต์) สำหรับ A. carbonarius TK4.2 พบว่า W. anomalus MSCU 0652 มีประสิทธิภาพในการยับยั้งการเจริญและการผลิตสารพิษจากราได้ดีที่สุดเมื่อเลี้ยงบนอาหารที่ค่าความเป็นกรด-เบสเท่ากับ 5 (82.42±2.76 เปอร์เซ็นต์) บ่มที่อุณหภูมิห้อง (81.20±2.65 เปอร์เซ็นต์) และค่าความเข้มข้นของอาหารเลี้ยงยีสต์ปกติ (83.88±0.32 เปอร์เซ็นต์) และลดการผลิตโอคราทอกซินเอได้ดีที่สุดเมื่อเลี้ยงบนอาหารที่ค่าความเป็นกรด-เบสเท่ากับ 5 (99.91±0.07 เปอร์เซ็นต์) บ่มที่อุณหภูมิห้อง (99.92±0.01 เปอร์เซ็นต์) และค่าความเข้มข้นของอาหารเลี้ยงยีสต์ปกติ (99.97±0.01 เปอร์เซ็นต์) นอกจากนี้ เมื่อทดสอบความสามารถในการลดการปนเปื้อนสารพิษจากราพบว่า ตะกอนเซลล์ยีสต์ที่ไม่มีชีวิตของ S. cerevisiae …

การผลิตสารลดแรงตึงผิวชีวภาพจาก Bacillus Velezensis B49 และการยับยั้งราก่อโรคพืช, สิรภพ ภูมิภูติกุล

Chulalongkorn University Theses and Dissertations (Chula ETD)

ราก่อโรคพืชสามารถทำลายผลผลิตทางการเกษตรได้ทั่วโลก การใช้วิธีทางชีวภาพสามารถลดการใช้สารเคมีในการกำจัดราก่อโรคพืชได้ ราก่อโรคพืชที่พบส่วนใหญ่ ได้แก่ Acremonium furcatum, Colletotrichum gloeosporioides, Fusarium moniliforme, Fusarium proliferatum, Fusarium solani, Phytophthora palmivora และ Pyricularia oryzae การศึกษาก่อนหน้านี้พบว่า Bacillus velezensis B49 สามารถยับยั้งราที่ก่อโรคในพืช และสามารถสร้างสารลดแรงตึงผิวชีวภาพได้ งานวิจัยนี้มีวัตถุประสงค์เพื่อเพิ่มการผลิตสารลดแรงตึงผิวชีวภาพจาก B. velezensis B49 และทดสอบการยับยั้งราก่อโรคพืชด้วยสารลดแรงตึงผิวชีวภาพที่ผลิตได้ ผลการทดสอบการยับยั้งการเจริญของราก่อโรคพืชโดยใช้เทคนิคการขีดเชื้อและเทคนิคผสมน้ำเลี้ยงเชื้อของ B. velezensis B49 แสดงความสามารถในการยับยั้งการเจริญของราต่อโรคพืชทั้ง 7 ชนิด ทดสอบสมบัติการผลิตสารลดแรงตึงผิวชีวภาพของ B. velezensis B49 โดยใช้ 4 วิธีที่แตกต่างกัน ได้แก่ การทดสอบการยุบตัวของน้ำเลี้ยงเชื้อบนฟิล์มน้ำมัน, การทดสอบการแตกของเม็ดเลือดแดง, การทดสอบการกระจายตัวของน้ำมัน และการทดสอบการเกิดอิมัลชัน พบว่า B. velezensis B49 ให้ผลบวกกับทั้ง 4 วิธี ซึ่งยืนยันได้ว่า B. velezensis B49 สามารถผลิตสารลดแรงตึงผิวชีวภาพได้ การทดสอบผลของความเป็นกรดเบสที่มีต่อสมบัติของสารลดแรงตึงผิวชีวภาพ พบว่าที่ความเป็นกรดเบสระหว่าง pH 2 – 10 ทำให้เกิดอิมัลชันไม่แตกต่างกัน แต่เมื่อความเป็นกรดเบสสูงขึ้น ส่งผลทำให้การเกิดอิมัลชันลดลงจนกระทั่งไม่เกิดอิมัลชันเลย ส่วนการทดสอบผลของอุณหภูมิที่มีต่อสมบัติของสารลดแรงตึงผิวชีวภาพของ B. velezensis B49 พบว่า อุณหภูมิไม่มีผลต่อสมบัติการเกิดอิมัลชัน การทดสอบผลของแหล่งคาร์บอนและไนโตรเจนที่มีต่อการผลิตสารลดแรงตึงผิวชีวภาพในอาหาร Mineral salt solution พบว่า B. velezensis B49 สามารถเจริญได้ในแหล่งคาร์บอน ได้แก่ กลูโคส, ฟรุกโทส และซูโครส ส่วนแหล่งไนโตรเจน ได้แก่ แอมโมเนียมไนเตรต และแอมโมเนียมซัลเฟต อย่างไรก็ตาม อาหารสูตรสมบูรณ์ให้ผลการเกิดอิมัลชันสูงกว่า ความสัมพันธ์ระหว่างการเจริญและการเกิดอิมัลชันต่อเวลา พบว่า B. velezensis B49 …

Functional Analysis Of Bacillus Anthracis Aspartate Transcarbamoylase And Dihydroorotase, Katelyn Leigh Schwager Silva

Wayne State University Theses

There are many enzymes required for efficient and proper pyrimidine biosynthesis. The two that are most important and were discussed in this thesis are aspartate transcarbamoylase (ATCase) and dihydroorotase (DHOase). Both play an important role in not only pyrimidine biosynthesis production, but also mechanistic regulation of de novo synthesis. Anthrax is an infection caused by Bacillus anthracis. Here we studied ATCase and DHOase in Bacillus Anthracis. In this thesis we understood the effects of the enzymes ATCase and DHOase on pyrimidine biosynthesis. Adequate inhibitors of these enzymes would result in cell death and could pose as a cure to infection …

A Comparative Study Of Equine Gut Microbiomes Using 16s And 18s Rrna Sequencing, Jillian Jorgenson

Undergraduate Honors Thesis Projects

The gut microbiome of domestic horses (Equus ferus caballus) can be broken down into two primary divisions of interest: (1) prokaryotic composition, consisting of bacteria and archaea and (2) fungal composition. Within the gut, there are also eukaryotic parasite communities that may interact with the microbiome. While each has been the subject of various scientific explorations, in this study we analyze the potential interconnectedness of these categories. To determine the extent to which each component of the gut microbiome/parasitic communities influences the other, DNA was extracted and amplified from the fecal samples of eight horses. A combination of …

Value Of Dedicated Research Time For Imgs In Obtaining Surgical Residency Training Positions: A 10-Year Review Of Applicants From A Medical College In Pakistan, Mohammad Raheel Jajja, Marvi Tariq, Salila Shoaib Hashmi, Thomas F. Dodson, Rashida Ahmed

Department of Pathology and Laboratory Medicine

Objective: International Medical Graduates (IMGs) secured greater than 10% of all general surgery (GS) residency positions in the US during the past decade. The Match process remains competitive, with a significant number of IMGs performing dedicated research before residency application. The impact of such research remains largely unknown. We aimed to provide an objective analysis of the impact of dedicated research time on obtaining a categorical GS residency position.
Design: Data for National Resident Matching Program Match results from 2008-2017 was compiled from annual Match lists of the Aga Khan University, Medical College (Karachi, Pakistan). Medical graduates provided this information …

Illumination Of The Golgi Apparatus Of Pathogenic And Nonpathogenic Naegleria Species, Tyler M. Poe

Theses and Dissertations

In this study, Naegleria fowleri, a pathogenic amoeba and the causative agent of Primary Amebic Meningoencephalitis (PAM), was utilized to determine the presence or absence of classically conserved Golgi molecules featured in the expression of a Golgi apparatus. Previous studies concluded no Golgi expression via light microscopy and transmission electron microscopy, but a recent report on Naegleria gruberi indicated the presence of dispersed Golgi tubules. Non-pathogenic species of the Naegleria genus such as Naegleria gruberi 30540 and Naegleria lovaniensis 30569 were utilized in Western immunoblot analysis compared to reduced whole-cell lysate proteins of two strains of N. fowleri and …

Preconditioning Of The Tumor Microenvironment By Means Of Low Dose Chemotherapies For An Effective Immunotherapy Of Breast Cancer, Hussein F. Aqbi

Theses and Dissertations

Breast cancer mortality is mainly due to distant recurrence of the disease arising from dormant tumor cells established by cancer therapies. Patients who initially respond to cancer therapies often succumb to distant recurrence of the disease. It is not clear why people with the same type of breast cancer respond to treatments differently; some escape from dormancy and relapse earlier than others. In addition, some tumor clones respond to immunotherapy while others do not. We investigated how autophagy plays a role in accelerating or delaying recurrence of neu overexpressing mouse mammary carcinoma (MMC) following adriamycin (ADR) treatment, and in affecting …

Response And Recovery Of Syntrophic And Methanogenic Activity To Saltwater Intrusion In A Tidal Freshwater Marsh Soil, David J. Berrier Jr.

Theses and Dissertations

Tidal freshwater wetland soils contain large amounts of organic carbon, some of which is mineralized to carbon dioxide (CO₂) and methane (CH₄) by a diverse consortium of anaerobic microorganisms that includes fermenters, syntrophs, and methanogens (MG). These microbial groups are tightly linked and often rely on cooperative interspecies metabolisms (i.e., syntrophy) to survive. Environmental perturbations can disrupt these interactions and thus alter the rates and pathways of carbon cycling. One environmental change of particular concern in coastal wetlands is sea level rise, which can result in increased episodic saltwater intrusion events into these ecosystems. These events …

The Infectivity Of Naegleria Fowleri Cysts In Vivo And In Vitro, And Mediation Of Encystment By Camp, Anna L. Evdokiou

Theses and Dissertations

The free-living amoeba and causative agent of Primary Amoebic Meningoencephalitis, Naegleria fowleri, has three life stages: the trophozoite, the flagellate, and the cyst. This study examined the ability of the cyst to attach to, excyst upon, and destroy cell cultures grown to confluent monolayers, and to cause Primary Amoebic Meningoencephalitis in a murine animal model. The co-culture of cysts with P388D.1, CHME3, Vero, human nasal epithelial, and rat primary mixed glial cells resulted in destruction of the monolayer of all cell types once the cysts attached and excysted. One day post exposure to cysts, the mixed glial cells exhibited …

Riparian Zone Soil Microbial Community Dynamics: Interactions With Nutrient Loadings, James Bannister

Theses and Dissertations (Comprehensive)

Riparian zones are a type of wetland described as the interface between land and a body of water such as a river or stream. Riparian zones are effective buffers against anthropogenic pollutants and nutrient loads from non-point sources that can greatly diminish water quality. Riparian zones can host a variety of plant species and associated microbial communities. The combined biological processes of plants, bacteria, and arbuscular mycorrhizal fungi (AMF) are key to nutrient cycling and nutrient removal in riparian zones. As such, understanding the factors that influence them is critical for watershed management. This research is targeted at obtaining a …