Virology Commons^™

Impact Of The Dose And The Number Of Transmitted/Founder Viruses On Siv Dynamics, Sunil Maity, Vitaly V. Ganusov

Biology and Medicine Through Mathematics Conference

No abstract provided.

Breaking Into Hiv-1'S Epigenetic Vault: Cure Strategies To Eliminate The Viral Reservoir, Joanna Jones, Chelsea Gunderson, Brian Wigdahl, Michael Nonnemacher

Kimmel Cancer Center Faculty Papers

Human immunodeficiency virus type 1 (HIV-1) is a retrovirus that integrates into the host cell's DNA as a provirus. Transcription from the provirus is regulated in large part by cellular proteins and epigenetic factors. These may be repressive or permissive to productive infection. The host factors that regulate this balance are therefore attractive targets for HIV-1 therapeutics. Indeed, proviral chromatin is the focus of two of the current HIV-1 cure strategies. "Shock and Kill" uses latency reversal agents to open the provirus's chromatin, promoting high levels of gene expression that induce the killing of infected cells. "Block and Lock" uses …

Surveillance Of A Novel Vesivirus Discovered In An Urban Mephitis Mephitis Population, Amanda E. Diggins

Honors Theses and Capstones

Caliciviridae is a family of non-enveloped, positive-sense, single stranded RNA viruses, including eleven defined genera that contain important pathogens of humans and animals. Within the Caliciviridae family, the genus Vesiviridae includes feline calicivirus, a leading cause of upper respiratory disease in cats, and vesicular exanthema of swine virus, a historical disease of domestic swine that has now been implicated in several marine mammal vesicular diseases, one of which has been confirmed zoonotic. Urban landscapes create a unique environment for rapid intra- and interspecies transmission of viruses. Clustered resources attract high-density populations of synanthropic wildlife species, increasing spatial overlap and heightening …

The Effect Of The Affordable Care Act Medicaid Expansion On The Risk Of Hospital Closure And Adolescent Hpv Immunization In Rural Counties, Juliette Des Rosiers

Scripps Senior Theses

From 2005 to 2025, over 200 rural hospitals shut their doors, often citing increased operational costs, staffing shortages, low patient volume, regulatory barriers, financial challenges exacerbated by the COVID-19 pandemic, and uncompensated care as common contributors to the closures. Rural patients are often referred by their primary care physician to a hospital for regular immunizations, since smaller clinics have less capacity to provide immunizations due to a shortage of pediatricians and limited vaccine stock. A crucial vaccine that is not required by schools and underutilized in rural areas is that against human papillomavirus (HPV), a virus that infects cutaneous and …

Development Of Broadly Protective Vaccines Against New World Arenaviruses, Brian B. Gowen

Funded Research Records

No abstract provided.

Culture-Independent Meta-Pangenomics Enabled By Long-Read Metagenomics Reveals Associations With Pediatric Undernutrition, Jeremiah J Minich, Nicholas Allsing, M Omar Din, Michael J Tisza, Kenneth Maleta, Daniel Mcdonald, Nolan Hartwick, Allen Mamerto, Caitriona Brennan, Lauren Hansen, Justin Shaffer, Emily R Murray, Tiffany Duong, Rob Knight, Kevin Stephenson, Mark J Manary, Todd P Michael

Faculty, Staff and Students Publications

The human gut microbiome is linked to child malnutrition, yet traditional microbiome approaches lack resolution. We hypothesized that complete metagenome-assembled genomes (cMAGs), recovered through long-read (LR) DNA sequencing, would enable pangenome and microbial genome-wide association study (GWAS) analyses to identify microbial genetic associations with child linear growth. LR methods produced 44-64× more cMAGs per gigabase pair (Gbp) than short-read methods, with PacBio (PB) yielding the most accurate and cost-effective assemblies. In a Malawian longitudinal pediatric cohort, we generated 986 cMAGs (839 circular) from 47 samples and applied this database to an expanded set of 210 samples. Machine learning identified species …

In Vitro Antiviral Activity Of Cat’S Claw (Uncaria Tomentosa) Bark Extract Against Human Influenza A Virus, Juliann N. Makau, Keith K. Talaam, Mike Odiwuor, Janet M. Majanja, Sophia Musenjeri, Ratika Rahmasari, Samoel A. Khamadi, Ken Watanabe

Pharmaceutical Sciences and Research

Influenza A viruses mutate very fast and this leads to the development of resistance to antivirals, hence the need to find new therapeutics. Due to their extensive traditional use, natural products are crucial resources for the discovery of drugs. Cat’s claw (Uncaria tomentosa), is a tropical vine known for various health benefits and in this study we evaluated its anti-influenza activity. Pulverized material of the stem bark was extracted using 80% ethanol, hot water, and 1% sodium bicarbonate. The extracts were dried and dissolved in dimethylsulfoxide before testing for cytotoxicity and antiviral activity using crystal violet assay. The …

Increasing Pediatric Hpv Vaccination Rates, Brooke A. Nicholas

Dissertations

Increasing Pediatric HPV Vaccination Rates

Abstract

Problem: The human papillomavirus (HPV) is a sexually transmitted infection that affects more than 80% of the population within the United States (Eisenhauer et al., 2020). HPV can develop into cervical, anogenital, and oropharyngeal cancers (Eisenhauer et al., 2020). About 4,000 individuals die from cervical cancer alone each year (O’Leary, 2022). The HPV vaccine, though recommended by the ACIP and AAP, is below national vaccination rates in comparison to other vaccines (O’Leary, 2022).

Methods: This quality improvement project is a non-randomized controlled trial that observed HPV vaccine dose completion rates for patients aged 9-14 …

Nasal Microbionts Differentially Colonize And Elicit Cytokines In Human Nasal Epithelial Organoids, Andrea I Boyd, Leah A Kafer, Isabel F Escapa, Amal Kambal, Hira Tariq, Susan G Hilsenbeck, Hoa Nguyen-Phuc, Anubama Rajan, Joshua M Lensmire, Kathryn A Patras, Pedro A Piedra, Sarah E Blutt, Katherine P Lemon

Faculty, Staff and Students Publications

Nasal colonization by Staphylococcus aureus or Streptococcus pneumoniae is associated with an increased risk of infection by these pathobionts, whereas nasal colonization by Dolosigranulum species is associated with health. Human nasal epithelial organoids (HNOs) differentiated at air-liquid interface (ALI) physiologically recapitulate human nasal respiratory epithelium with a robust mucociliary blanket. Due to their natural stem-like properties, HNO lines are a long-term experimental resource that offers genetic diversity based on the different donors. To develop HNOs as a new model system for bacterial nasal colonization, we reproducibly monocolonized HNOs differentiated at ALI with S. aureus, S. pneumoniae, or Dolosigranulum …

Strain-Specific Variability In Viral Kinetics, Cytokine Response, And Cellular Damage In Air-Liquid Cultures Of Human Nasal Organoids After Infection With Sars-Cov-2, Gina M Aloisio, Trevor J Mcbride, Letisha Aideyan, Emily M Schultz, Ashley M Murray, Anubama Rajan, Erin G Nicholson, David Henke, Laura Ferlic-Stark, Amal Kambal, Hannah L Johnson, Elina A Mosa, Fabio Stossi, Sarah E Blutt, Pedro A Piedra, Vasanthi Avadhanula

Faculty, Staff and Students Publications

SARS-CoV-2 variants have demonstrated distinct epidemiological patterns and clinical presentations throughout the COVID-19 pandemic. Understanding variant-specific differences at the respiratory epithelium is crucial for understanding their pathogenesis. Here, we utilized human nasal organoid air-liquid interface (HNO-ALI) cell cultures to compare the viral replication kinetics, innate immune response, and epithelial damage of six different strains of SARS-CoV-2 (B.1.2, WA, Alpha, Beta, Delta, and Omicron). All variants replicated efficiently in HNO-ALIs, but with distinct replication kinetic patterns. The Delta variant exhibited delayed replication kinetics, achieving a steady state at 6 days post-infection compared to 3 days for other variants. Cytokine analysis revealed …

Exploring The Transformative Effects Of Calorie Restriction On The Lacrimal Gland In Adult Mice, Olivier Mauduit, Prashant Kumar, Kaitlin K Scholand, Emre Aksan, Laura Schaefer, Anmar Abu-Romman, Vanessa Delcroix, Zhiyuan Yu, Aude I Sindikubwabo, Ron Korstanje, Helen P Makarenkova, Cintia S De Paiva

Faculty, Staff and Students Publications

Advanced age is one of the most recognizable risk factors for dry eye. Dry eye disease affects millions worldwide and can result from age-related lacrimal gland dysfunction, which correlates with a decline in lacrimal gland secretory cell function and chronic inflammation. This study investigated the potential of calorie restriction to maintain lacrimal gland and ocular surface health. Adult female C57BL/6 J mice were subjected to a 40% calorie restriction for 4 months, starting at 6-7 months and continuing until 10-11 months. These mice were compared to controls fed ad libitum. Bulk RNA sequencing of lacrimal glands, conjunctiva, and cornea subjected …

Results Of Tor001: An Open-Label Single Patient Study Using Targeted Bacteriophage Therapy For The Treatment Of A Chronic Urinary Tract Infection, Jonathan D Cook, Payton B Hooey, Keiko C Salazar, Justin R Clark, Umesh Jain, Carlos Fernando, Hanjeong Harvey, Alexander Cervantes, Stephanie Omagari, Udi Blankstein, Andrew M Kropinski, Alan R Davidson, Karen L Maxwell, Lori L Burrows, Austen L Terwilliger, Anthony W Maresso, Greg J German

Faculty, Staff and Students Publications

Chronic urinary tract infections are persistent bacterial infections with the potential to drive antibiotic resistance. Like other persistent bacterial infections, intracellular bacterial reservoirs and biofilm formation hinder the clearance of pathogens despite long courses of antibiotic therapy. New strategies for treatment of these persistent infections are needed. Here we describe the results of an open-label individual patient study using bacteriophage therapy to treat a chronic urinary tract infection in an immunocompetent 72-year-old woman without underlying urolithiasis or indwelling devices. We co-administered HP3.1, HP3, and ES19 bacteriophages with demonstrated in vitro activity via bladder instillation, orally, and as a topical formulation. …

Elephant Endotheliotropic Herpesvirus 2 Infection In 5 African Elephants (Loxodonta Africana) At Multiple North American Zoological Institutions, Taylor J Willis, Anne Burgdorf-Moisuk, Maren Connolly, Jan Raines, Cameron Ratliff, Zoltan S Gyimesi, Erica Lipanovich, Genevive A Dumonceaux, Kathryn L Perrin, Lauren L Howard, Matthew E Kinney, Kirk Suedmeyer, Erin Latimer, Tiffany L Kim, Jessica R Watts, Jie Tan, Paul Ling

Faculty, Staff and Students Publications

Objective: To acknowledge that elephant endotheliotropic herpesvirus (EEHV) is a well-recognized major threat to Asian elephants (Elephas maximus) and can cause acute and often fatal hemorrhagic disease (HD). Historically, EEHV-HD has been less frequently identified in African elephants (Loxodonta africana). This case series describes 5 recent cases of EEHV2 infection in African elephants within managed care at 5 North American institutions.

Animals: 5 African elephants (L africana).

Clinical presentation: The cases involved 4-, 7-, and 10-year-old males that died despite receiving aggressive medical therapy and 4- and 14-year-old females that survived. Clinical signs included lethargy, decreased appetite, lameness, changes in …

Enhancing Preparedness: A Genetic Study Of Sar-Cov-2 And Other Microbial Public Health Threats In Wastewater From A College Town, Christian N. Hutchinson

Master's Theses

Problem

The SARS-CoV-2 (COVID-19) pandemic revealed both the systemic vulnerabilities of our healthcare system as well as the importance of timely, localized data for informing public health responses. Traditional testing approaches were essential but often failed to capture the full extent of viral spread, especially in those with mild or asymptomatic conditions that relied on at home testing. This underreporting hindered effective allocation of resources and made developing effective intervention strategies difficult. We also realized the potential for wastewater surveillance to be applied to tracking antimicrobial resistance gene markers. Taken together, this approach should have important implications for improving public …

Increased Fungal Burden In The Gastrointestinal Tract Of Brain-Dead Organ Donors, Erika J Nachman, Colleen K Ardis, A Kyle B Ardis, Javier Nieto, Madeline M Bresson, Clare M Robertson, Maggie N Seale, Nora M Villafuerte, Zhe Lyu, Eva C Preisner, Heather A Danhof, Sara C Di Rienzi, Yolanda T Becker, Robert A Britton

Faculty, Staff and Students Publications

Approximately 3% of organ transplant recipients will be diagnosed with an invasive fungal infection (IFI), with 10%-47% being fatal. The source of IFI is typically not known, but Candida spp. cause the majority of IFI cases. We obtained intestines from two types of organ donors, brain-dead (BD) (n = 7) and donation after circulatory death (DCD) (n = 5), to sample microbes from the mucosal surface and the lumen. BD donors were parenterally fed and treated with corticosteroids in the days before procurement, whereas DCD donors were enterally fed and not given corticosteroids. We found fungi present in …

Three Things We Can Do Now To Reduce The Risk Of Avian Influenza Spillovers, Kenneth B Yeh, William P Bahnfleth, Elaine Bradford, Carol Cardona, Kristen K Coleman, Peter J Hudson, Bernadeta Dadonaite, Rebecca J Hutchins, Anthony Maresso, C Raina Macintyre, Matthew Scotch

Faculty, Staff and Students Publications

No abstract provided.

Dietary Lipids Induce Ppard And Bcl6 To Repress Macrophage Il-23 Induction After Intestinal Injury And Lps Exposure, Ashleigh M Gil, Daniel F Zegarra-Ruiz, Wan-Jung Wu, Kendra Norwood, Adrien Assie, Buck S Samuel, Angela M Major, Gretchen E Diehl, Andrea A Hill Mcalester

Faculty, Staff and Students Publications

Unresolved tissue damage is a common feature of Inflammatory Bowel Disease (IBD) that facilitates disease progression. Here, we showed that high animal fat diets (HFD), an environmental risk factor associated with IBD pathogenesis, suppress intestinal macrophage production of critical tissue repair responses after damage. This includes reduced IL-23 production, which drives downstream production of IL-22, which is needed for barrier repair. Indicating that dietary lipids interfere with responses to microbial molecules needed to induce barrier protective functions, we found oleic acid could directly suppress macrophage Il23a induction after lipopolysaccharide (LPS) treatment. Deleting the lipid transporter CD36 on macrophages restored the …

Oral Dosing Of The Nucleoside Analog Obeldesivir Is Efficacious Against Rsv Infection In African Green Monkeys, Jared Pitts, J Lizbeth Reyes Zamora, Savrina Manhas, Thomas Aeschbacher, Josolyn Chan, Vincent Cutillas, Varsha Nair, Nicholas C Riola, Arya Vijjapurapu, Meghan S Vermillion, Stacey Eng, Christopher Richards, Dong Han, Jason K Perry, Subhra Chaudhuri, Szu-Wen Liu, Clarissa Martinez, Nadine Peinovich, Kai-Hui Sun, Arthur Cai, Ross Martin, Jasmine Moshiri, Charlotte Hedskog, Darius Babusis, Dustin S Siegel, Rao Kalla, Vasanthi Avadhanula, Pedro A Piedra, Kim Stobbelaar, Peter L Delputte, Caleb Marceau, Roberto Mateo, Evguenia Maiorova, Hongmei Mo, Raju Subramanian, Richard L Mackman, Tomas Cihlar, Simon P Fletcher, John P Bilello

Faculty, Staff and Students Publications

Respiratory syncytial virus (RSV) is a significant cause of morbidity and mortality in high-risk populations. Although prophylactic options are available, there are no effective oral therapeutics for RSV infection. Obeldesivir (ODV) is an orally bioavailable prodrug of the nucleoside analog GS-441524, which is converted intracellularly to its active nucleoside triphosphate and inhibits the RSV RNA polymerase. Here we report the potent antiviral activity of ODV against geographically and temporally diverse RSV A and B clinical isolates (EC50: 0.20–0.66 μM). Resistance selection studies with ODV and GS-441524 against RSV identify a single amino acid substitution, I777L, in the L polymerase with …

Microbial Biosensor For Sensing And Treatment Of Intestinal Inflammation, Duolong Zhu, Jeffrey Galley, Jason Pizzini, Elena Musteata, Martin V Douglas, Walter J Chazin, Eric P Skaar, Jeffrey J Tabor, Robert A Britton

Faculty, Staff and Students Publications

Synthetic biology has enabled the development of biosensors to detect intestinal inflammation, yet few target the clinically validated biomarker of intestinal inflammation calprotectin with both diagnostic and therapeutic capabilities. Here, an optimized calprotectin biosensor is presented that leverages a zinc uptake regulator (Zur) controlled promoter coupled with a memory circuit to detect and record intestinal inflammation in vivo. The level of biosensor activation strongly correlates with calprotectin levels in the colon of two independent mouse models of colitis. Coupling of the biosensor with the production of the anti-inflammatory cytokine IL10 allowed for the resolution of chemically induced colitis, demonstrating the …

Unfolding The Mystery Of Autoimmunity: The Environmental Determinants Of Diabetes In The Young (Teddy) Study, Marian Rewers, Daniel Agardh, Suzanne Bennett Johnson, Ezio Bonifacio, Helena Elding Larsson, Patricia Gesualdo, William Hagopian, Michael J Haller, Heikki Hyöty, Randi Johnson, Richard Mcindoe, Eoin Mckinney, Jessica Melin, Åke Lernmark, Richard E Lloyd, Kristian F Lynch, Jill M Norris, Stephen S Rich, Roswith Roth, Desmond Schatz, Jorma Toppari, Eric Triplett, Kendra Vehik, Suvi M Virtanen, Anette-G Ziegler, Beena Akolkar, Jeffrey P Krischer, Teddy Study Group

Faculty, Staff and Students Publications

In 2025, the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) at the National Institutes of Health celebrates 75 years of leadership in diabetes research. The NIDDK serves people of the U.S. affected by or at risk for many chronic diseases, including diabetes and other endocrine, metabolic, and digestive disorders, by funding innovative research to develop better treatment and prevention and a cure for these conditions. Autoimmunity that leads to type 1 diabetes or celiac disease or thyroid autoimmunity affects 1 in 20 children and adolescents in the U.S. While treatments are available, prevention of these common autoimmune …

Knowledge Of Hiv Transmission And Prevention Among University Students In Pakistan: A Cross-Sectional Study, Muhammad Saleem, Sajid Masood, Shahid Hussain

Journal of Bioresource Management

HIV/AIDS remains a significant public health problem internationally, with young adults being especially at risk because of behavioral and knowledge deficits. In Pakistan, cultural inhibitions and suboptimal health education are the main reasons for limited awareness, particularly among university students. This study had the objectives of determining the knowledge level about HIV transmission and prevention among undergraduate students in Kohsar University Murree (KUM) and to investigate correlations with salient demographic variables. A cross-sectional survey was carried out among 510 students aged 18-27 years through a pre-validated, standardized questionnaire with 12 knowledge-based items. Descriptive statistics and Chi-square tests were utilized to …

Phage-Induced Protection Against Lethal Bacterial Reinfection, Yikun Xing, Haroldo J Hernandez Santos, Ling Qiu, Samantha R Ritter, Jacob J Zulk, Rachel Lahowetz, Kathryn A Patras, Austen L Terwilliger, Anthony W Maresso

Faculty, Staff and Students Publications

Bacteriophages, or phages, are viruses that target and infect bacteria. Due to a worldwide rise in antimicrobial resistance (AMR), phages have been proposed as a promising alternative to antibiotics for the treatment of resistant bacterial infections. Up to this point in history, phage use in preclinical animal studies, clinical trials, and emergency-use compassionate care cases has centered around the original observation from 1915 showing phage as lytic agent, and thus a treatment that kills bacteria. Here, we describe an activity associated with phage therapy that extends beyond lytic activity that results in long-term protection against reinfection. This activity is potent, …

Aged Regulatory T Cells Fail To Control Autoimmune Lacrimal Gland Pathogenic Cd4+ T Cells, Kaitlin K Scholand, Laura Schaefer, Gowthaman Govindarajan, Zhiyuan Yu, Jeremias G Galletti, Cintia S De Paiva

Faculty, Staff and Students Publications

CD25KO mice are a model of Sjögren disease. CD25KO mice have severe inflammation and infiltrating lymphocytes to the lacrimal glands (LG). Whether the pathogenicity of CD25KO CD4+ T cells can be controlled in vivo by Tregs is unknown. Eight-week-old B6 and CD25KO mice LGs were submitted for RNA bulk sequencing. A total of 3481 genes were differentially expressed in CD25KO LG compared to B6. Tear washing analysis identified CD25KO mice had elevated protein levels of TNF, IFN-γ, and CCL5 and decreased protein levels of IL-12p40 and VEGF-A. Co-adoptive transfer of CD25KO CD4+ T cells with either young or aged B6 …

Viral Detection In Anterior Nasal Swabs Versus Nasopharyngeal Swabs In Children, Nicole Neeley, Abby Kietzman, Rangaraj Selvarangan, Dithi Banerjee, Jennifer Goldman, Jennifer Schuster

Research Days

Background: Respiratory viruses are a significant cause of pediatric illness and healthcare utilization. Diagnostic testing for respiratory viruses is generally performed using nasopharyngeal (NP) specimens obtained by trained staff, limiting testing to medical settings. Evaluating additional sampling methods in children that are easier to collect and can be performed outside of medical settings, such as anterior nasal swab (NS) specimens may expand access to diagnostic testing and aid public health surveillance.

Methods: Eligible children hospitalized at Children’s Mercy Hospital who had a standard of care NP specimen collected for respiratory viral testing were enrolled. Research NS specimens were obtained through …

Expanding Inducible Epithelial Resistance Against Pneumonia: Novel Virus, Novel Receptor, Michael Longmire

Dissertations and Theses (Open Access)

Pneumonia is the leading infectious cause of death worldwide and presents a continuing risk among immunocompromised patients. Our work has been focused for many years on the phenomenon of inducible epithelial resistance, where activation of the innate immune response in the airway epithelium is necessary and sufficient to produce a pathogen-killing but self-protective environment to prevent severe disease. Inducible resistance is pathogen-agnostic and has been demonstrated against an array of respiratory infections. We achieve this using a combination of pattern recognition receptor agonists – Pam2CSK4 and ODN M362 being the current formulation – which produce synergistic levels of pathogen reduction …

Bibliometric Analysis Of Research Trends Related To Human Immunodeficiency Virus., Madyson E. Johnson, Kaitlyn R. Coffman, Valerie Rivas, Elizabeth Barrett

ATU Scholars Symposium

Human immunodeficiency virus poses major health burden across the globe including the United States of America and has its zoonotic origin from the Simian Immunodeficiency viruses of sooty mangabey monkey and chimpanzee in Africa. Epidemiological trends indicate that even though the mortality rates for HIV are falling globally, the rates of new cases have been rising since 2010 in several countries including the USA. An estimated 0.5% of the human population is currently infected with the virus with countries like USA, India, Nigeria and South Africa carrying the highest burden of the disease. Host receptors such as CD4 and coreceptors …

Limosilactobacillus Reuteri Promotes The Expression And Secretion Of Enteroendocrine- And Enterocyte-Derived Hormones, Sara C Di Rienzi, Heather A Danhof, Micah D Forshee, Ari Roberts, Robert A Britton

Faculty, Staff and Students Publications

Intestinal microbes can beneficially impact host physiology, prompting investigations into the therapeutic usage of such microbes in a range of diseases. For example, human intestinal microbe Limosilactobacillus reuteri strains ATCC PTA 6475 and DSM 17938 are being considered for use for intestinal ailments, including colic, infection, and inflammation, as well as for non-intestinal ailments, including osteoporosis, wound healing, and autism spectrum disorder. While many of their beneficial properties are attributed to suppressing inflammatory responses, we postulated that L. reuteri may also regulate intestinal hormones to affect physiology within and outside of the gut. To determine if L. reuteri secreted factors …

The Design, Construction, And Testing Of Mrna Vaccine Against Equine Herpes Virus, Bhawana Devkota

LSU Master's Theses

Equine Herpesvirus-1 (EHV 1) is a worldwide significant pathogen that causes respiratory illness, abortion, and neurological disorders in equine. Current vaccines, including live attenuated, inactivated, and subunit platforms, do not prevent viral latency, mucosal shedding, or cross-strain immunity, requiring alternative approaches. To address these gaps, this project explores the design, synthesis, and in vitro testing of an mRNA vaccine targeting immunogenic EHV 1 glycoprotein (gB, gC, gD, gG, and gM). Epitopes were computationally predicted using the Immune Epitope Database (IEDB), codon-optimized for Bos taurus, and cloned into pUCIDT vectors using SP6/T7 promoters. In vitro transcription (IVT) used nucleotide modifications …

Emerging Clostridioides Difficile Ribotypes Have Divergent Metabolic Phenotypes, Firas S Midani, Heather A Danhof, Nathanael Mathew, Colleen K Ardis, Kevin W Garey, Jennifer K Spinler, Robert A Britton

Faculty, Staff and Students Publications

Clostridioides difficile is a gram-positive spore-forming pathogen that commonly causes diarrheal infections in the developed world. Although C. difficile is a genetically diverse species, certain ribotypes are overrepresented in human infections, and it is unclear if metabolic adaptations are essential for the emergence of these epidemic ribotypes. To identify ribotype-specific metabolic differences, we therefore tested carbon substrate utilization by 88 C. difficile isolates and looked for differences in growth between 22 ribotypes. As expected, C. difficile was capable of growing on a variety of carbon substrates. Further, C. difficile strains clustered by phylogenetic relationship and displayed ribotype-specific and clade-specific …

Control Of Clostridioides Difficile Virulence And Physiology By The Flagellin Homeostasis Checkpoint Flic-Fliw-Csra In The Absence Of Motility, Duolong Zhu, Katherine J Wozniak, Firas Midani, Shaohui Wang, Xingmin Sun, Robert A Britton

Faculty, Staff and Students Publications

Mutations affecting Clostridioides difficile flagellin (FliC) have been shown to be hypervirulent in animal models and display increased toxin production and alterations in central metabolism. The regulation of flagellin levels in bacteria is governed by a tripartite regulatory network involving fliC, fliW, and csrA, which creates a feedback system to regulate flagella production. Through genomic analysis of C. difficile clade 5 strains (non-motile), we identified they have jettisoned many of the genes required for flagellum biosynthesis yet retain the major flagellin gene fliC and regulatory gene fliW. We therefore investigated the roles of fliC, fliW …