Microbiology Commons^™

Understanding And Quantifying Bioaerosol Fate Within The Aerobiological Pathway: Physical Transport, Environmental Decay, And Mitigation, Sean Kinahan

Theses & Dissertations

The recent COVID-19 pandemic has highlighted the need for better tools to understand and characterize phases of the aerobiological pathway, a model for understanding how infectious bioaerosols are sourced, generated, transported, deposit, and affect human health. This dissertation presents validation of methodologies for studying transport of airborne biological agents and variations on their consequences, especially focusing on their physical and chemical fate. Chapter 1 focuses on a parallel comparison of two methods of aging bioaerosols in real-world outdoor environments with complex sunlight, atmospheric chemistry, and pollutants. Both capture on microfibers and the use of Goldberg rotating drums to keep a …

Author Correction: Membrane Translocation Process Revealed By In Situ Structures Of Type Ii Secretion System Secretins, Zhili Yu, Yaoming Wu, Muyuan Chen, Tong Huo, Wei Zheng, Steven J Ludtke, Xiaodong Shi, Zhao Wang

Faculty, Staff and Students Publications

No abstract provided.

Investigating Transcriptional Anomalies During Persistence In Chlamydia Trachomatis, Nathan D. Hatch

Theses & Dissertations

Chlamydia trachomatis (Ctr) is the leading cause of bacterial sexually transmitted infections. Ctr, a Gram-negative, obligate intracellular bacterium, develops within a membrane-bound vacuole termed an inclusion. This protective, nutrient rich, intracellular environment has allowed Ctr to undergo extensive reductive evolution – resulting in a streamlined genome of approximately 1 Mbp and the loss or fragmentation of several biosynthetic pathways, including the ability to synthesize tryptophan (Trp) de novo. During infection, the host immune system releases the cytokine IFNγ. Upon binding to a host cell, IFNγ stimulates the expression of indoleamine-2,3-dioxygenase, an enzyme capable of catabolizing cytosolic Trp, thereby starving …

Evaluation Of The Virulence Potential Of Avian Pathogenic Escherichia Coli Isolated From Broiler Breeders With Colibacillosis In Mississippi, Jiddu Joseph

Theses and Dissertations

Avian pathogenic Escherichia coli (APEC) is a bacterium that is responsible for colibacillosis in birds. However, information about broiler breeder APEC isolates is limited, but the data is critical due to the transfer of this bacteria down the production pyramid to progenies resulting in high mortality. Therefore, we evaluated the phenotypic virulence characteristics of 28 isolates using embryo lethality and day-old chick challenge assays. Also, the in vitro adhesion and invasion potential of selected nine isolates were identified. Results showed more than 1/3^rd of the isolates were highly virulent and the virulence increased as the number of virulence-associated genes …

Nutritional Strategies To Reduce Salmonella Enteritidis Infections In Laying Hens: Prebiotic, Probiotic, And Precision Biotics, Ishab Poudel

Theses and Dissertations

Salmonella Enteritidis (SE) infections in laying hens is a significant cause of foodborne illness linked to the consumption of contaminated eggs. This dissertation encompasses novel strategies aimed to explore appropriate in-vitro and in-vivo models to evaluate the effects of these novel strategies to reduce SE in laying hens. Firstly, we investigated the potential probiotics, prebiotics, and essential oil combinations to reduce SE in-vitro. The results showed that probiotics and prebiotics are equally effective to reduce SE. In subsequent studies, we evaluated the role of vaccination history on cecal microbiota and SE infections with various doses of oral SE challenge. …

Analyzing Pseudomonas Aeruginosa With Bacteriophage Tags Using Photoacoustic Flow Cytometry, Jennifer C. Schinke

Electronic Theses and Dissertations

The number of daily bacterial infections is climbing and the CDC explains that this is due to the antibiotic-resistant threat in the United States. Finding a faster way of bacterial identification is necessary as it currently takes 1-4 days for a medical lab to culture and identify bacteria. Photoacoustic flow cytometry (PAFC) can be used as an alternative method resulting in swift identification within an hour (Edgar, 2019). Pseudomonas aeruginosa, cell line PA01, will be coated in up to a few hundred red dyed phages making it detectible by the photoacoustic flow cytometry system. Bacteriophages (phages) are viruses that …

Microsporidian Spores And The Integrin Binding Loop Of The Madam Protein Are Important For Integrin Signaling And Attachment To Host Cells, Cindy L. Barrett

Electronic Theses and Dissertations

Microsporidia are a distant fungal pathogen that have severe clinical consequences for the immunocompromised. Previous work identified a microsporidian pathogen protein termed Microsporidian ADAM or MADAM. This protein has close sequence homology to other ADAM proteins (A Disintegrin and Metalloproteinase) in two microsporidian species, Encephalitozoon intestinalis and E. cuniculi. ADAM proteins have a wide range of functions, including binding to integrins and host signaling. It is known that many pathogens manipulate integrins to invade host cells, and it is predicted that microsporidia are also exploiting this host target. Previous work with the MADAM protein demonstrated that this protein has a …

Heterogeneity Of The Group B Streptococcal Type Vii Secretion System And Influence On Colonization Of The Female Genital Tract, Brady L Spencer, Alyx M Job, Clare M Robertson, Zainab A Hameed, Camille Serchejian, Caitlin S Wiafe-Kwakye, Jéssica C Mendonça, Morgan A Apolonio, Prescilla E Nagao, Melody N Neely, Natalia Korotkova, Konstantin V Korotkov, Kathryn A Patras, Kelly S Doran

Faculty, Staff and Students Publications

Type VIIb secretion systems (T7SSb) in Gram-positive bacteria facilitate physiology, interbacterial competition, and/or virulence via EssC ATPase-driven secretion of small ɑ-helical proteins and toxins. Recently, we characterized T7SSb in group B Streptococcus (GBS), a leading cause of infection in newborns and immunocompromised adults. GBS T7SS comprises four subtypes based on variation in the C-terminus of EssC and the repertoire of downstream effectors; however, the intraspecies diversity of GBS T7SS and impact on GBS-host interactions remains unknown. Bioinformatic analysis indicates that GBS T7SS loci encode subtype-specific putative effectors, which have low interspecies and inter-subtype homology but contain similar domains/motifs and therefore …

Hunger Extends Lifespan By Modulating Histone Proteins, Hailan Liu, Hongjie Li, Yong Xu

Faculty, Staff and Students Publications

No abstract provided.

Investigating The Physiological Mechanisms Between Resistance Training And Pain Relief In The Cancer Population: A Literature Review, Yvonne Jiang, Peter C. Angeletti, Amy J. Hoffman

Nebraska Center for Virology: Faculty Publications

This literature review examines the mechanisms of how exercise, specifically in the form of resistance training, may lead to pain relief in the cancer population. Primary data from three different cancer populations: breast, prostate, and lung, will be examined. A number of experimental studies have been conducted to confirm the effectiveness of resistance training on pain relief as well as the biochemical pathways that relate to this process. In this review, we will examine 5 randomized controlled trials. For the purposes of this review, pain is defined as physical suffering or discomfort associated with illness. Pain is the body’s natural …

Sars‑Cov‑2 Entry Into And Evolution Within A Skilled Nursing Facility, Nicole R. Sexton, Parker Parker Cline, Emily N. Gallichotte, Emily Fitzmeyer, Michael C. Young, Ashley J. Janich, Kristy L. Pabilonia, Nicole Ehrhart, Gregory D. Ebel

Nebraska Center for Virology: Faculty Publications

SARS-CoV-2 belongs to the family Coronaviridae which includes multiple human pathogens that have an outsized impact on aging populations. As a novel human pathogen, SARS-CoV-2 is undergoing continuous adaptation to this new host species and there is evidence of this throughout the scientific and public literature. However, most investigations of SARS-CoV-2 evolution have focused on largescale collections of data across diverse populations and/or living environments. Here we investigate SARS-CoV-2 evolution in epidemiologically linked individuals within a single outbreak at a skilled nursing facility beginning with initial introduction of the pathogen. The data demonstrate that SARSCoV- 2 was introduced to the …

Microbe Hunters, Paul De Kruif

Zea E-Books Collection

Microbe Hunters by Paul de Kruif was first published in 1926 by Harcourt, Brace and Company, New York. It dramatically recounts the breakthrough discoveries of the fundamental elements of bacteriology. It features exciting profiles of Antony Leeuwenhoek, Lazzaro Spallanzani, Louis Pasteur, Robert Koch, Émile Roux, Emil Behring, Élie Metchnikoff, Theobald Smith, David Bruce, Ronald Ross, Battista Grassi, Walter Reed, and Paul Ehrlich. Their development of germ theory and its scientific proofs led to the first effective treatments for human diseases like anthrax, rabies, diptheria, malaria, sleeping sickness, syphilis, and yellow fever. They also made discoveries that saved the dairy, wine, …

Evaluating Vaccine Management Strategies For Edwardsiella Ictaluri Infections In Zebrafish (Danio Rerio), Brandy Malbrough

LSU Master's Theses

Aquaculture is a globally important industry that faces significant challenges due to infectious diseases, which can result in substantial financial losses. In 2011, a new strain of Edwardsiella ictaluri emerged as a major pathogen affecting zebrafish in the ornamental fish industry, leading to high mortality rates and posing a severe threat to the sector. Vaccines provide potential benefits for disease prevention in aquaculture, particularly live-attenuated vaccines (LAVs), which induce strong host immune responses. Bacterial attenuation for vaccine development has evolved from serial passage to more targeted genetic modification techniques. However, regulatory constraints limit the availability of licensed LAVs for aquaculture. …

Roving Methyltransferases Generate A Mosaic Epigenetic Landscape And Influence Evolution In Bacteroides Fragilis Group, Michael J Tisza, Derek D N Smith, Andrew E Clark, Jung-Ho Youn, Pavel P Khil, John P Dekker

Faculty, Staff and Students Publications

Three types of DNA methyl modifications have been detected in bacterial genomes, and mechanistic studies have demonstrated roles for DNA methylation in physiological functions ranging from phage defense to transcriptional control of virulence and host-pathogen interactions. Despite the ubiquity of methyltransferases and the immense variety of possible methylation patterns, epigenomic diversity remains unexplored for most bacterial species. Members of the Bacteroides fragilis group (BFG) reside in the human gastrointestinal tract as key players in symbiotic communities but also can establish anaerobic infections that are increasingly multi-drug resistant. In this work, we utilize long-read sequencing technologies to perform pangenomic (n = …

Yes-Associated Protein-1 Overexpression In Ocular Surface Squamous Neoplasia; A Potential Diagnostic Marker And Therapeutic Target, Peter Julius, Stepfanie N. Siyumbwa, Fred Maate, Phyllis Moonga, Guobin Kang, Trevor Kaile, John T. T., Charles Wood

Nebraska Center for Virology: Faculty Publications

Yes-associated protein-1 (YAP-1) is a Hippo system transcription factor, which serves as an oncogene in squamous cell carcinoma, and several solid tumors when the Hippo pathway is dysregulated. Yet, the activity of YAP-1 in ocular surface squamous neoplasia (OSSN) has not been determined. Here, we investigate the relationship between YAP-1 overexpression and OSSN. Using a cross-sectional study design, we recruited 227 OSSN patients from the University Teaching Hospitals in Lusaka, Zambia. Immunohistochemistry was used to assess YAP-1 protein overexpression in tumor tissue relative to surrounding benign squamous epithelium. OSSN patient samples (preinvasive, n = 62, 27% and invasive, n = …

Nac1 Confines Virus‐Specific Memory Formation Of Cd4+ T Cells Through The Rock1‐Mediated Pathway, Liqing Wang, Hao-Yun Peng, Jugal Kishore Das, Anil Kumar, Yijie Ren, Darby J. Ballard, Xiaofang Xiong, Wen Yang, Xingcong Ren, Paul De Figueiredo, Jin-Ming Yang, Jianxun Song

Markey Cancer Center Faculty Publications

Nucleus accumbens‐associated protein 1 (NAC1), a transcriptional cofactor, has been found to play important roles in regulating regulatory T cells, CD8 + T cells, and antitumor immunity, but little is known about its effects on T‐cell memory. In this study, we found that NAC1 expression restricts memory formation of CD4 + T cells during viral infection. Analysis of CD4 + T cells from wild‐type (WT) and NAC1‐ deficient (−/−) mice showed that NAC1 is essential for T‐cell metabolism, including glycolysis and oxidative phosphorylation, and supports CD4 + T‐cell survival in vitro. We further demonstrated that a deficiency of NAC1 downregulates …

Exploring The Interactions Between Sars-Cov-2 And Host Proteins, Sojan Shrestha

School of Biological Sciences: Dissertations, Theses, and Student Research

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the current pandemic, Coronavirus Disease 2019 (COVID-19). SARS-CoV-2 is considered to be of zoonotic origin; it originated in non-human animals and was transmitted to humans. Since the early stage of the pandemic, however, the evidence of transmissions from humans to animals (reverse zoonoses) has been found in multiple animal species including mink, white-tailed deer, and pet and zoo animals. Furthermore, secondary zoonotic events of SARS-CoV-2, transmissions from animals to humans, have been also reported. It is suggested that non-human hosts can act as SARS-CoV-2 reservoirs where accumulated …

Longitudinal Analysis Of The Evolution Of Cellular Immunity To Sars-Cov-2 Induced By Infection And Vaccination, Spyridoula Vasileiou, Manik Kuvalekar, Yovana Velazquez, Ayumi Watanabe, Mansi Narula, Aster G Workineh, Matthew French-Kim, Alejandro Torres Chavez, Sarah Gilmore, Cliona M Rooney, Ann M Leen

Faculty, Staff and Students Publications

No abstract provided.

Vincristine/Irinotecan/Temsirolimus Upfront Window Treatment Of High-Risk Hepatoblastoma: A Report From The Children’S Oncology Group Ahep0731 Study Committee, Patrick A Thompson, Marcio H Malogolowkin, Wayne L Furman, Jin Piao, Mark D Krailo, Nadia Chung, Lindsay Brock, Alexander J Towbin, Elizabeth B Mccarville, Milton J Finegold, Sarangarajan Ranganathan, Stephen P Dunn, Max R Langham, Eugene D Mcgahren, Gregory M Tiao, Christopher B Weldon, Allison F O'Neill, Carlos Rodriguez-Galindo, Rebecka L Meyers, Howard M Katzenstein

Faculty, Staff and Students Publications

Background: Survival for children with metastatic hepatoblastoma (HB) remains suboptimal. We report the response rate and outcome of two courses of vincristine/irinotecan/temsirolimus (VIT) in children with high-risk (HR)/metastatic HB.

Procedures: Patients with newly diagnosed HB received HR window chemotherapy if they had metastatic disease or a serum alpha-fetoprotein (AFP) level less than 100 ng/mL. Patients received vincristine (days 1 and 8), irinotecan (days 1-5), and temsirolimus (days 1 and 8). Cycles were repeated every 21 days. Responders had either a 30% decrease using RECIST (Response Evaluation Criteria in Solid Tumors) criteria OR a 90% (>1 log10 decline) AFP decline …

A Review On Antibiotic Resistance And The Use Of Medicinal Plants In The Management Of Uropathogenic Bacteria, Hubza Ruatt Khan, Mehvish Javeed, Iqra Batool, Rabeea Anwar, Asma Ashraf, Sara Janiad

Journal of Bioresource Management

UTIs are the most prevalent infections and are caused by uropathogenic microbes such as Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Staphylococcus aureus, and Enterococcus spp. Antibiotic resistance has hampered the management of UTIs over the years, with direct repercussions on the treatment cost, the infection severity, and the duration of hospitalization. This review discussed the route of infections, risk factors connected to UTIs, antibiotic resistance issues as well as an alternative therapy to overcome the problem of antibiotic resistance. The medicinal plants, which have been utilized for thousands of years to cure a variety of ailments, represent a …

Assessment Of Antimicrobial Competence Of Epiphytes And Endophytes From Osmium Basilicum And Trigonella Foenum Graecum, Iram Asim, Atia Iqbal, Muhammad Ikrama Tanveer

Journal of Bioresource Management

Plant-associated bacteria are an unexplored group of microorganisms that has enormous potential. These bacteria are the source of finding new antimicrobial substances. The present study aimed to isolate and characterize the epiphytes and endophytes from Osmium basilicum and Trigonella foenum graecum plants and to determine their antimicrobial potential against pathogenic bacteria from Nishtar Hospital Multan, Pakistan. The sum of 18 stems and roots along leaf specimens were assembled as of the plant's Osmium basilicum plus Trigonella foenum graecum as of the distinct locales of the Multan city. Overall 73 bacterial strains were isolated and their colony morphology, gram staining, spore …

The Pros Of Changing Trna Identity, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The notion that errors in protein synthesis are universally harmful to the cell has been questioned by findings that suggest such mistakes may sometimes be beneficial. However, how often these beneficial mistakes arise from programmed changes in gene expression as opposed to reduced accuracy of the translation machinery is still unclear. A new study published in JBC shows that some bacteria have beneficially evolved the ability to mistranslate specific parts of the genetic code, a trait that allows improved antibiotic resistance.

Complete Genome Sequences Of 37 Bacteria From The Human Vaginal Tract, Christopher Whidbey, Alyssa N Konopaski, Robel Teshome, Sejal Dhaliwal, M Quinn Peters, Marlyd E Mejia, Mallory B Ballard, Kathryn A Patras

Faculty, Staff and Students Publications

Microorganisms colonizing the human vaginal mucosa are associated with healthy states, as well as conditions such as bacterial vaginosis and infection-associated preterm birth. Here, we report complete genome sequences of 37 bacterial isolates from the human vaginal tract.

History Of Childhood Physical Abuse Is Associated With Gut Microbiota Diversity Among Adult Psychiatric Inpatients, Jessica C Rohr, Katelynn A Bourassa, Dominique S Thompson, J Christopher Fowler, B Christopher Frueh, Benjamin L Weinstein, Joseph Petrosino, Alok Madan

Faculty, Staff and Students Publications

BACKGROUND: Traumatic life events are associated with the development of psychiatric and chronic medical illnesses. This exploratory study examined the relationship between traumatic life events and the gut microbiota among adult psychiatric inpatients.

METHODS: 105 adult psychiatric inpatients provided clinical data and a single fecal sample shortly after admission. A modified version of the Stressful Life Events Screening Questionnaire was used to quantify history of traumatic life events. 16S rRNA gene sequencing was used to analyze the gut microbial community.

RESULTS: Gut microbiota diversity was not associated with overall trauma score or any of the three trauma factor scores. Upon …

Viral Dna Accumulation Regulates Replication Efficiency Of Chlorovirus Osy-Ne5 In Two Closely Related Chlorella Variabilis Strains, Ahmed Esmael, Irina V. Agarkova, David D. Dunigan, You Zhou, James L. Van Etten

Nebraska Center for Virology: Faculty Publications

Many chloroviruses replicate in Chlorella variabilis algal strains that are ex-endosymbionts isolated from the protozoan Paramecium bursaria, including the NC64A and Syngen 2-3 strains. We noticed that indigenous water samples produced a higher number of plaque-forming viruses on C. variabilis Syngen 2-3 lawns than on C. variabilis NC64A lawns. These observed differences led to the discovery of viruses that replicate exclusively in Syngen 2-3 cells, named Only Syngen (OSy) viruses. Here, we demonstrate that OSy viruses initiate infection in the restricted host NC64A by synthesizing some early virus gene products and that approximately 20% of the cells produce a …

Improving Microbiome Research Through Enhanced Reporting And Modeling The Effects Of Antibiotic Usage, Chloe A. Mirzayi

Dissertations and Theses

I consider two key areas in the growing field of human microbiome research: improving the quality of study reporting and the impact of antibiotics on participants in human gut microbiome research studies. In the first chapter, a team of evaluators used the Strengthening the Organization and Reporting of Microbiome Studies (STORMS) checklist to assess recently published microbiome literature. I found moderate agreement and reliability between evaluators, identified several items in STORMS that could be improved, and confirmed that the STORMS checklist can serve as a tool for assessing the reporting quality of published microbiome study. The next chapter considers pre-exposure …

Understanding Ubiquitin-Like Signaling At The Host-Pathogen Interface, Danna Eloisa Guzman Gonzalez

University Honors Theses

Research on pathogen intervention and ubiquitin modification has increased over the last few years but a lot is still unknown about ubiquitin-like modifiers (Ubl) and how or if they are modified by pathogens in the same way as Ubiquitin. In this work, two different studies conducted over the course of 2 years are highlighted. The first study focused on purifying and synthesizing four activity based probes in order to study enzymatic activity in the Ubl-modification systems. These probes were reacted with virulence factors isolated from different bacteria and it was concluded that there were unexpected bands formed between some of …

The Influence Of Microorganisms On Human Health, Tiffany Bui

University Honors Theses

The purpose of this thesis is to explore the interplay between the environment, lifestyle, and composition of human microbiomes across different communities, with a specific focus on immune and digestive health. This literature review investigates three distinct types of communities: isolated/traditional, transitional, and urban/industrialized communities, each characterized by unique environments, societal structures, and interactions. These factors contribute to the distinct microbial populations and compositions within each community. It is impossible to avoid contact with microorganisms as they are present in every aspect of our lives, from the air we breathe, the water we drink, the soil we walk on, the …

Investigating The Mammillary Bodies As An Early Target Of Alzheimer's Disease, Cole Martinson

University Honors Theses

Alzheimer's disease (AD) is the most common form of dementia. With minimal treatment options and no cure, developing a deeper understanding of the pathology of the disease is crucial. For nearly four decades, the accumulation of beta-amyloid (Aβ) plaques has been correlated with the disease and its progression. Previous studies mapping this accumulation show that the mammillary bodies (MB) are an early target of the disease. Glutamatergic neurons are of key interest due to their prevalence in the central nervous system, specifically the MB. To understand the effects of AD on the glutamatergic system, we used vesicular glutamate transporter 2 …

Characterization Of Immunomodulatory Properties Of Manuka Honey: Potential Mitigation Against Colon Cancer, Razan Jamil Masad

Dissertations

The focus on using alternative natural products for cancer prevention and treatment has been increasing over the past decade. Among these natural products, Manuka honey (MH) has been extensively investigated for its antimicrobial, wound healing, and anticancer effects. The current study aimed to characterize the immunomodulatory capacity of MH using both in vitro and in vivo approaches and investigate its potential to modulate anti-tumor immune responses in a preclinical model of colorectal cancer. We demonstrate that MH can directly act on macrophages to induce gene expression of several inflammatory cytokines and chemokines and the production of TNF-a, a major proinflammatory …