Microbiology Commons^™

The Efficiency Of P27 Cleavage During In Vitro Respiratory Syncytial Virus (Rsv) Infection Is Cell Line And Rsv Subtype Dependent, Wanderson Rezende, Xunyan Ye, Laura S Angelo, Alexandre F Carisey, Vasanthi Avadhanula, Pedro A Piedra

Faculty, Staff and Students Publications

Respiratory syncytial virus (RSV) fusion protein (F) is highly conserved between subtypes A and B (RSV/A and RSV/B). To become fully active, F precursor undergoes enzymatic cleavage to yield F1 and F2 subunits and releases a 27-amino-acid peptide (p27). Virus-cell fusion occurs when RSV F undergoes a conformational change from pre-F to post-F. Previous data show that p27 is detected on RSV F, but questions remain regarding if and how p27 affects the conformation of mature RSV F. Monoclonal antibodies against p27, site Ø (pre-F specific), and site II were used to monitor RSV F conformation by enzyme-linked immunosorbent assay …

Elucidating The Impact Of Sos-Response Timing In On Escherichia Coli Survival Following Treatment With Fluoroquinolone Topoisomerase Inhibitors, Stephanie Schofield

Honors Scholar Theses

Antibiotic treatment failure is a public health crisis, with a 2019 report stating that roughly 35,000 deaths occur in the United States yearly due to bacterial infections that are unresponsive to antibiotics (1). One complication in the treatment of bacterial infection is antibiotic persistence which further compromises our battle to effectively treat infection. Bacterial persisters can exist in clonal bacterial cultures and can tolerate antibiotic treatment by undergoing reversible phenotypic changes. They can survive drug concentrations that their genetically identical kin cannot. Some persisters remain in a slow growing state and are difficult to target with current antibiotics. A specific …

Exercise Reprograms The Inflammatory Landscape Of Multiple Stem Cell Compartments During Mammalian Aging, Ling Liu, Soochi Kim, Matthew T Buckley, Jaime M Reyes, Jengmin Kang, Lei Tian, Mingqiang Wang, Alexander Lieu, Michelle Mao, Cristina Rodriguez-Mateo, Heather D Ishak, Mira Jeong, Joseph C Wu, Margaret A Goodell, Anne Brunet, Thomas A Rando

Faculty, Staff and Students Publications

Exercise has the ability to rejuvenate stem cells and improve tissue regeneration in aging animals. However, the cellular and molecular changes elicited by exercise have not been systematically studied across a broad range of cell types in stem cell compartments. We subjected young and old mice to aerobic exercise and generated a single-cell transcriptomic atlas of muscle, neural, and hematopoietic stem cells with their niche cells and progeny, complemented by whole transcriptome analysis of single myofibers. We found that exercise ameliorated the upregulation of a number of inflammatory pathways associated with old age and restored aspects of intercellular communication mediated …

Effect Of Temperature On The Microbiome Of A Laboratory Reared Colony Of Haemaphysalis Longicornis Ticks, Brianna Mitchell

Poster Presentations

Honors research poster.

Haemaphysalis longicornis is a species of tick native to eastern Asia, including eastern China, Japan, eastern Russia, and Korea. To date, it has invaded and has now established its existence in Australia, New Zealand, and several of the Pacific Islands. This species of tick has recently been introduced to the United States, having a confirmed sighting in November 2017 on a sheep farm in New Jersey and since establishing populations in 18 states along the east coast and Appalachia. Based on the existing locations of H. longicornis in its native regions, as well as in the United …

Diagnosis Of Urinary Tract Infections And Rapid Molecular Characterization Of Antibiotic Resistance, Mohammed Harris

All Dissertations

Urinary tract infections (UTIs) are one of the most common infectious clinical entities in both community and hospital settings. They have a broad range of clinical severity yet inflict large epidemiological burden of morbidity and mortality on patients and the healthcare system with billions of dollars in cost of treatment. Understanding what methods are optimal for diagnosing UTIs are critical to mitigate the marked impact and cost of these infections.

Chapter 1 and 2 in this work surveys the broad array of diagnostic modalities for UTIs and highlights their advantages and limitations in the context of the current standard of …

Interspecies Interactions Within The Host: The Social Network Of Group B Streptococcus, Marlyd E Mejia, Clare M Robertson, Kathryn A Patras

Faculty, Staff and Students Publications

Group B Streptococcus (GBS) is a pervasive neonatal pathogen accounting for a combined half a million deaths and stillbirths annually. The most common source of fetal or neonatal GBS exposure is the maternal microbiota. GBS asymptomatically colonizes the gastrointestinal and vaginal mucosa of 1 in 5 individuals globally, although its precise role in these niches is not well understood. To prevent vertical transmission, broad-spectrum antibiotics are administered to GBS-positive mothers during labor in many countries. Although antibiotics have significantly reduced GBS early-onset neonatal disease, there are several unintended consequences, including an altered neonatal microbiota and increased risk for other microbial …

Acute High-Fat Diet Impairs Macrophage-Supported Intestinal Damage Resolution, Andrea A Hill, Myunghoo Kim, Daniel F Zegarra-Ruiz, Lin-Chun Chang, Kendra Norwood, Adrien Assié, Wan-Jung H Wu, Michael C Renfroe, Hyo Wong Song, Angela M Major, Buck S Samuel, Joseph M Hyser, Randy S Longman, Gretchen E Diehl

Faculty, Staff and Students Publications

Chronic exposure to high-fat diets (HFD) worsens intestinal disease pathology, but acute effects of HFD in tissue damage remain unclear. Here, we used short-term HFD feeding in a model of intestinal injury and found sustained damage with increased cecal dead neutrophil accumulation, along with dietary lipid accumulation. Neutrophil depletion rescued enhanced pathology. Macrophages from HFD-treated mice showed reduced capacity to engulf dead neutrophils. Macrophage clearance of dead neutrophils activates critical barrier repair and antiinflammatory pathways, including IL-10, which was lost after acute HFD feeding and intestinal injury. IL-10 overexpression restored intestinal repair after HFD feeding and intestinal injury. Macrophage exposure …

Severe Acute Respiratory Syndrome Coronavirus 2 (Sars-Cov-2) Testing And Detection During Peripartum Hospitalizations Among A Multicenter Cohort Of Pregnant Persons: March 2020-February 2021, Miranda J Delahoy, Flor Munoz, De-Kun Li, Carmen Sofia Arriola, Nanette Lee Bond, Michael Daugherty, Jeannette Ferber, Nickolas Ferguson, Louise Hadden, Jillian T Henderson, Stephanie A Irving, Mary Juergens, Venkatesh Kancharla, Mara Greenberg, Roxana Odouli, Gabriella Newes-Adeyi, Erin G Nicholson, Lawrence Reichle, Momodou Sanyang, Margaret Snead, Fatimah S Dawood, Allison L Naleway

Faculty, Staff and Students Publications

BACKGROUND: Identifying severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections during peripartum hospitalizations is important to guide care, implement prevention measures, and understand infection burden.

METHODS: This cross-sectional analysis used electronic health record data from hospitalizations during which pregnancies ended (peripartum hospitalizations) among a cohort of pregnant persons at 3 US integrated healthcare networks (sites 1-3). Maternal demographic, medical encounter, SARS-CoV-2 testing, and pregnancy and neonatal outcome information was extracted for persons with estimated delivery and pregnancy end dates during March 2020-February 2021 and ≥1 antenatal care record. Site-stratified multivariable logistic regression was used to identify factors associated with testing …

Ifn-Γ Production By Brain-Resident Cells Activates Cerebral Mrna Expression Of A Wide Spectrum Of Molecules Critical For Both Innate And T Cell-Mediated Protective Immunity To Control Reactivation Of Chronic Infection With Toxoplasma Gondii, Yasuhiro Suzuki, Jenny Lutshumba, Kuey Chu Chen, Mohamed H. Abdelaziz, Qila Sa, Eri Ochiai

Markey Cancer Center Faculty Publications

We previously demonstrated that brain-resident cells produce IFN-g in response to reactivation of cerebral infection with Toxoplasma gondii. To obtain an overall landscape view of the effects of IFN-g from brain-resident cells on the cerebral protective immunity, in the present study we employed NanoString nCounter assay and quantified mRNA levels for 734 genes in myeloid immunity in the brains of T and B cell-deficient, bone marrow chimeric mice with and without IFN-g production by brain-resident cells in response to reactivation of cerebral T. gondii infection. Our study revealed that IFN-g produced by brain-resident cells amplified mRNA expression for the molecules …

Broad Protective Vaccination Against Systemic Escherichia Coli With Autotransporter Antigens, Yikun Xing, Justin R Clark, James D Chang, Dylan M Chirman, Sabrina Green, Jacob J Zulk, Joseph Jelinski, Kathryn A Patras, Anthony W Maresso

Faculty, Staff and Students Publications

Extraintestinal pathogenic Escherichia coli (ExPEC) is the leading cause of adult life-threatening sepsis and urinary tract infections (UTI). The emergence and spread of multidrug-resistant (MDR) ExPEC strains result in a considerable amount of treatment failure and hospitalization costs, and contribute to the spread of drug resistance amongst the human microbiome. Thus, an effective vaccine against ExPEC would reduce morbidity and mortality and possibly decrease carriage in healthy or diseased populations. A comparative genomic analysis demonstrated a gene encoding an invasin-like protein, termed sinH, annotated as an autotransporter protein, shows high prevalence in various invasive ExPEC phylogroups, especially those associated with …

Baloxavir Safety And Clinical And Virologic Outcomes In Influenza Virus-Infected Pediatric Patients By Age Group: Age-Based Pooled Analysis Of Two Pediatric Studies Conducted In Japan, Nobuo Hirotsu, Hiroki Sakaguchi, Keita Fukao, Satoshi Kojima, Pedro A Piedra, Kenji Tsuchiya, Takeki Uehara

Faculty, Staff and Students Publications

BACKGROUND: Anti-influenza treatment is important for children and is recommended in many countries. This study assessed safety, clinical, and virologic outcomes of baloxavir marboxil (baloxavir) treatment in children based on age and influenza virus type/subtype.

METHODS: This was a post hoc pooled analysis of two open-label non-controlled studies of a single weight-based oral dose of baloxavir (day 1) in influenza virus-infected Japanese patients aged < 6 years (n = 56) and ≥ 6 to < 12 years (n = 81). Safety, time to illness alleviation (TTIA), time to resolution of fever (TTRF), recurrence of influenza illness symptoms and fever (after day 4), virus titer, and outcomes by polymerase acidic protein variants at position I38 (PA/I38X) were evaluated.

RESULTS: Adverse events were reported in 39.0 and 39.5% of patients < 6 years and ≥ 6 to < 12 years, respectively. Median (95% confidence interval) TTIA was 43.2 (36.3-68.4) and 45.4 (38.9-61.0) hours, and TTRF was 32.2 (26.8-37.8) and 20.7 (19.2-23.8) hours, for patients < 6 years and ≥ 6 to < 12 years, respectively. Symptom and fever recurrence was more common in patients < 6 years with influenza B (54.5 and 50.0%, respectively) compared with older patients (0 and 25.0%, respectively). Virus titers declined (day 2) for both age groups. Transient virus titer increase and PA/I38X-variants were more common for patients < 6 years.

CONCLUSIONS: The safety and effectiveness of single-dose baloxavir were observed in children across all age groups and influenza virus types. Higher rates of fever recurrence …

Differential Co-Expression Networks Of The Gut Microbiota Are Associated With Depression And Anxiety Treatment Resistance Among Psychiatric Inpatients, Dominique S Thompson, Chenlian Fu, Tanmay Gandhi, J Christopher Fowler, B Christopher Frueh, Benjamin L Weinstein, Joseph Petrosino, Julia K Hadden, Marianne Carlson, Cristian Coarfa, Alok Madan

Faculty, Staff and Students Publications

BACKGROUND: Comorbid anxiety and depression are common and are associated with greater disease burden than either alone. Our recent efforts have identified an association between gut microbiota dysfunction and severity of anxiety and depression. In this follow-up, we applied Differential Co-Expression Analysis (DiffCoEx) to identify potential gut microbiota biomarker(s) candidates of treatment resistance among psychiatric inpatients.

METHODS: In a sample of convenience, 100 psychiatric inpatients provided clinical data at admission and discharge; fecal samples were collected early during the hospitalization. Whole genome shotgun sequencing methods were used to process samples. DiffCoEx was used to identify clusters of microbial features significantly …

Proposing An Rna Interference (Rnai)-Based Treatment For Human Immunodeficiency Virus (Hiv) By Analyzing The Post-Transcriptional Gene Targeting Of Sars-Cov-2, Hepatitis C Virus, And A549 Lung Cancer Cells, Arjun Jagdeesh

Undergraduate Research Posters

Human Immunodeficiency Virus (HIV) is a retrovirus that infects CD4+ T cell lymphocytes in humans, leading to the development of Acquired Immunodeficiency Syndrome (AIDS) if left untreated. While current treatment methods, including antiretroviral combination treatments, effectively limit HIV replication, HIV can evade these treatments due to its high mutation rate. Long-term antiretroviral treatment can also be toxic to patients, meaning patients would benefit from a new mechanism of HIV treatment. RNA interference (RNAi) is an antiviral pathway found in mammals, plants, and insects that involves a small-interfering RNA that is incorporated into a protein complex called the RNA-induced Silencing Complex …

The Rsv F P27 Peptide: Current Knowledge, Important Questions, Wanderson Rezende, Hadley E Neal, Rebecca E Dutch, Pedro A Piedra

Faculty, Staff and Students Publications

Respiratory syncytial virus (RSV) remains a leading cause of hospitalizations and death for young children and adults over 65. The worldwide impact of RSV has prioritized the search for an RSV vaccine, with most targeting the critical fusion (F) protein. However, questions remain about the mechanism of RSV entry and RSV F triggering and fusion promotion. This review highlights these questions, specifically those surrounding a cleaved 27 amino acids long peptide within F, p27.

Diversity And Evolution Of Computationally Predicted T Cell Epitopes Against Human Respiratory Syncytial Virus, Jiani Chen, Swan Tan, Vasanthi Avadhanula, Leonard Moise, Pedro A Piedra, Anne S De Groot, Justin Bahl

Faculty, Staff and Students Publications

Human respiratory syncytial virus (RSV) is a major cause of lower respiratory infection. Despite more than 60 years of research, there is no licensed vaccine. While B cell response is a major focus for vaccine design, the T cell epitope profile of RSV is also important for vaccine development. Here, we computationally predicted putative T cell epitopes in the Fusion protein (F) and Glycoprotein (G) of RSV wild circulating strains by predicting Major Histocompatibility Complex (MHC) class I and class II binding affinity. We limited our inferences to conserved epitopes in both F and G proteins that have been experimentally …

Comparing The Microbiomes Of Dental Plaques In 19th Century Ancestral Remains, Ananya Udyaver

Undergraduate Research Posters

During the construction of VCU’s Hermes A. Kontos Medical Sciences Building in April 1994, nineteenth century ancestral remains were found in an abandoned well on the Medical College of Virginia (MCV) campus. This well, now known as the East Marshall Street Well (EMSW), is thought to have been used as a disposal location for cadaver dissection for surgical and other medical waste in the past. VCU is now seeking to use DNA sequencing technology to match and assemble bones from each individual for a proper burial, uncover the cultural and historical context in which these people lived, and bring a …

Abnormalities In Cardiac And Inflammatory Biomarkers In Ambulatory Subjects After Covid-19 Infection, Joshua A Keefe, Vasanthi Avadhanula, Erin G Nicholson, Sridevi Devaraj, Pedro A Piedra, Biykem Bozkurt, Xander H T Wehrens

Faculty, Staff and Students Publications

BACKGROUND: Coronavirus-2019 (COVID-19) is known to affect the heart and is associated with a pro-inflammatory state. Most studies to date have focused on clinically sick subjects. Here, we report cardiac and proinflammatory biomarkers levels in ambulatory young adults with asymptomatic or mild COVID-19 infection compared to those without infection 4-8 weeks after severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) testing.

METHODS: 131 asymptomatic or mildly symptomatic subjects were enrolled following testing for SARS-COV-2. Fifty subjects tested negative, and 81 subjects tested positive. Serum samples were collected for measurement of C-reactive protein, ferritin, interleukin-6, NT-pro-B-type natriuretic peptide, and cardiac troponin 28-55 …

Clinical And In Vitro Evidence Favoring Immunoglobulin Treatment Of A Chronic Norovirus Infection In A Patient With Common Variable Immunodeficiency, Jeroen J A Van Kampen, Virgil A S H Dalm, Pieter L A Fraaij, Bas B Oude Munnink, Claudia M E Schapendonk, Ray W Izquierdo-Lara, Nele Villabruna, Khalil Ettayebi, Mary K Estes, Marion P G Koopmans, Miranda De Graaf

Faculty, Staff and Students Publications

BACKGROUND: Immunocompromised individuals can become chronically infected with norovirus, but effective antiviral therapies are not yet available.

METHODS: Treatments with nitazoxanide, ribavirin, interferon alpha-2a, and nasoduodenally administered immunoglobulins were evaluated sequentially in an immunocompromised patient chronically infected with norovirus. In support, these components were also applied to measure norovirus inhibition in intestinal enteroid cultures in vitro. Viral RNA levels were determined in fecal and plasma samples during each treatment and viral genomes were sequenced.

RESULTS: None of the antivirals resulted in a reduction of viral RNA levels in feces or plasma. However, during ribavirin treatment, there was an increased accumulation …

Butyrate-Producing Bacteria And Insulin Homeostasis: The Microbiome And Insulin Longitudinal Evaluation Study (Miles), Jinrui Cui, Gautam Ramesh, Martin Wu, Elizabeth T Jensen, Osa Crago, Alain G Bertoni, Chunxu Gao, Kristi L Hoffman, Patricia A Sheridan, Kari E Wong, Alexis C Wood, Yii-Der I Chen, Jerome I Rotter, Joseph F Petrosino, Stephen S Rich, Mark O Goodarzi

Faculty, Staff and Students Publications

Gut microbiome studies have documented depletion of butyrate-producing taxa in type 2 diabetes. We analyzed associations between butyrate-producing taxa and detailed measures of insulin homeostasis, whose dysfunction underlies diabetes in 224 non-Hispanic Whites and 129 African Americans, all of whom completed an oral glucose tolerance test. Stool microbiome was assessed by whole-metagenome shotgun sequencing with taxonomic profiling. We examined associations among 36 butyrate-producing taxa (n = 7 genera and 29 species) and insulin sensitivity, insulin secretion, disposition index, insulin clearance, and prevalence of dysglycemia (prediabetes plus diabetes, 46% of cohort), adjusting for age, sex, BMI, and race. The genus Coprococcus …

Maternal Gut Microbiota Mediate Intergenerational Effects Of High-Fat Diet On Descendant Social Behavior, Claudia M Di Gesù, Lisa M Matz, Ian J Bolding, Robert Fultz, Kristi L Hoffman, Antonella Marino Gammazza, Joseph F Petrosino, Shelly A Buffington

Faculty, Staff and Students Publications

Dysbiosis of the maternal gut microbiome during pregnancy is associated with adverse neurodevelopmental outcomes. We previously showed that maternal high-fat diet (MHFD) in mice induces gut dysbiosis, social dysfunction, and underlying synaptic plasticity deficits in male offspring (F1). Here, we reason that, if HFD-mediated changes in maternal gut microbiota drive offspring social deficits, then MHFD-induced dysbiosis in F1 female MHFD offspring would likewise impair F2 social behavior. Metataxonomic sequencing reveals reduced microbial richness among female F1 MHFD offspring. Despite recovery of microbial richness among MHFD-descendant F2 mice, they display social dysfunction. Post-weaning Limosilactobacillus reuteri treatment increases the abundance of short-chain …

Pathogenesis Of Tobacco-Associated Lung Adenocarcinoma Is Closely Coupled With Changes In The Gut And Lung Microbiomes, Casey T Finnicum, Zahraa Rahal, Maya Hassane, Warapen Treekitkarnmongkol, Ansam Sinjab, Rhiannon Morris, Yuejiang Liu, Elizabeth L Tang, Sarah Viet, Jason L Petersen, Philip L Lorenzi, Lin Tan, Joseph Petrosino, Kristi L Hoffman, Junya Fujimoto, Seyed Javad Moghaddam, Humam Kadara

Faculty, Staff and Students Publications

Microbial dysbiosis has emerged as a modulator of oncogenesis and response to therapy, particularly in lung cancer. Here, we investigate the evolution of the gut and lung microbiomes following exposure to a tobacco carcinogen. We performed 16S rRNA-Seq of fecal and lung samples collected prior to and at several timepoints following (nicotine-specific nitrosamine ketone/NNK) exposure in Gprc5a^−/− mice that were previously shown to exhibit accelerated lung adenocarcinoma (LUAD) development following NNK exposure. We found significant progressive changes in human-relevant gut and lung microbiome members (e.g., Odoribacter, Alistipes, Akkermansia, and Ruminococus) that are closely associated with …

Novel Technologies To Characterize And Engineer The Microbiome In Inflammatory Bowel Disease, Alba Boix-Amorós, Hilarly Monaco, Elisa Sambataro, Jose C. Clemente

Publications and Research

We present an overview of recent experimental and computational advances in technology used to characterize the microbiome, with a focus on how these developments improve our understanding of inflammatory bowel disease (IBD). Specifically, we present studies that make use of flow cytometry and metabolomics assays to provide a functional characterization of microbial communities. We also describe computational methods for strain-level resolution, temporal series, myco - biome and virome data, co-occurrence networks, and compositional data analysis. In addition, we review novel techniques to therapeutically manipulate the microbiome in IBD. We discuss the benefits and drawbacks of these technologies to increase awareness …

Phage Resistance Accompanies Reduced Fitness Of Uropathogenic Escherichia Coli In The Urinary Environment, Jacob J Zulk, Justin R Clark, Samantha Ottinger, Mallory B Ballard, Marlyd E Mejia, Vicki Mercado-Evans, Emmaline R Heckmann, Belkys C Sanchez, Barbara W Trautner, Anthony W Maresso, Kathryn A Patras

Faculty, Staff and Students Publications

Urinary tract infection (UTI) is among the most common infections treated worldwide each year and is caused primarily by uropathogenic Escherichia coli (UPEC). Rising rates of antibiotic resistance among uropathogens have spurred a consideration of alternative treatment strategies, such as bacteriophage (phage) therapy; however, phage-bacterial interactions within the urinary environment are poorly defined. Here, we assess the activity of two phages, namely, HP3 and ES17, against clinical UPEC isolates using in vitro and in vivo models of UTI. In both bacteriologic medium and pooled human urine, we identified phage resistance arising within the first 6 to 8 h of coincubation. …

Integrated Relationship Of Nasopharyngeal Airway Host Response And Microbiome Associates With Bronchiolitis Severity, Michimasa Fujiogi, Yoshihiko Raita, Marcos Pérez-Losada, Robert J Freishtat, Juan C Celedón, Jonathan M Mansbach, Pedro A Piedra, Zhaozhong Zhu, Carlos A Camargo, Kohei Hasegawa

Faculty, Staff and Students Publications

Bronchiolitis is a leading cause of infant hospitalizations but its immunopathology remains poorly understood. Here we present data from 244 infants hospitalized with bronchiolitis in a multicenter prospective study, assessing the host response (transcriptome), microbial composition, and microbial function (metatranscriptome) in the nasopharyngeal airway, and associate them with disease severity. We investigate individual associations with disease severity identify host response, microbial taxonomical, and microbial functional modules by network analyses. We also determine the integrated relationship of these modules with severity. Several modules are significantly associated with risks of positive pressure ventilation use, including the host-type I interferon, neutrophil/interleukin-1, T cell …

The Roles Of Gut Microbiome And Plasma Metabolites In The Associations Between Abo Blood Groups And Insulin Homeostasis: The Microbiome And Insulin Longitudinal Evaluation Study (Miles), Ruifang Li-Gao, Kirk Grubbs, Alain G Bertoni, Kristi L Hoffman, Joseph F Petrosino, Gautam Ramesh, Martin Wu, Jerome I Rotter, Yii-Der Ida Chen, Anne M Evans, Richard J Robinson, Laura Sommerville, Dennis Mook-Kanamori, Mark O Goodarzi, Gregory A Michelotti, Patricia A Sheridan

Faculty, Staff and Students Publications

Non-O blood groups are associated with decreased insulin sensitivity and risk of type 2 diabetes. A recent study pinpointed the associations between ABO blood groups and gut microbiome, which may serve as potential mediators for the observed increased disease risks. We aimed to characterize associations between ABO haplotypes and insulin-related traits as well as potential mediating pathways. We assessed insulin homeostasis in African Americans (AAs; n = 109) and non-Hispanic whites (n = 210) from the Microbiome and Insulin Longitudinal Evaluation Study. The ABO haplotype was determined by six SNPs located in the ABO gene. Based on prior knowledge, …

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

Electronic Theses and Dissertations

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

Salivary Biomarker Evaluation Of Chronic Pancreatitis Patients Reveals Alterations In Human Proteins, Cytokines, Prostaglandin E2 Levels, And Bacterial Diversity, Richard T Waldron, Elaina K Jones, Vincent I Anani, Jolaine M Hines, Jing Zhao, Aurelia Lugea, Marcio A Diniz, Sungjin Kim, Aida Habtezion, Kristi L Hoffman, Joseph F Petrosino, William E Fisher, Liang Li, Ryan J Lennon, Ravinder Jit Singh, Santhi Swaroop Vege, Stephen J Pandol, Mark D Topazian

Faculty, Staff and Students Publications

OBJECTIVES: Chronic pancreatitis (CP) is a chronic fibroinflammatory condition of the pancreas difficult to diagnose in early stages. Novel biomarkers useful to facilitate early diagnosis or treatment responses may be found in biofluids. Although saliva can be easily and noninvasively collected from patients, useful salivary biomarkers from CP patients have not yet been identified.

METHODS: Here, we analyzed the proteome by quantitative proteomics, cytokine/chemokine levels by Luminex analysis, prostaglandin E2 (PGE2) levels by a mass spectrometry-based assay, and bacterial species diversity by 16S ribosomal ribonucleic acid sequencing in saliva samples from confirmed CP patients and healthy controls.

RESULTS: Our results …

Genomic And Functional Characterization Of Vancomycin-Resistant Enterococci-Specific Bacteriophages In The Galleria Mellonella Wax Moth Larvae Model, Lynn El Haddad, Georgios Angelidakis, Justin R Clark, Jesus F Mendoza, Austen L Terwilliger, Christopher P Chaftari, Mark Duna, Serena T Yusuf, Cynthia P Harb, Mark Stibich, Anthony Maresso, Roy F Chemaly

Faculty, Staff and Students Publications

Phages are naturally occurring viruses that selectively kill bacterial species without disturbing the individual’s normal flora, averting the collateral damage of antimicrobial usage. The safety and the effectiveness of phages have been mainly confirmed in the food industry as well as in animal models. In this study, we report on the successful isolation of phages specific to Vancomycin-resistant Enterococci, including Enterococcus faecium (VREfm) and Enterococcus faecalis from sewage samples, and demonstrate their efficacy and safety for VREfm infection in the greater wax moth Galleria mellonella model. No virulence-associated genes, antibiotic resistance genes or integrases were detected in …

Molecular Mechanisms Underlying Mucosal Attachment And Colonization By Clostridioides Difficile, Ben Sidner

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Clostridioides difficile is a Gram-positive, spore-forming, anaerobic bacterium which causes gastrointestinal disease and is a leading cause of nosocomial infections. Although infection typically occurs following antibiotic therapy, in recent years there has been an increase in infections which are not preceded by antibiotic use. Additionally, community-associated infections and rates of disease recurrence have increased. While it is understood that a healthy gastrointestinal microbiota provides protection against infection, the molecular mechanisms which underly C. difficile's ability to colonize and persist in the gut are mostly unknown. Building on work from others that suggests C. difficile associates with the outer mucus …

Dietary Fatty Acid Intake And The Colonic Gut Microbiota In Humans, Anthony A Xu, Luke K Kennedy, Kristi Hoffman, Donna L White, Fasiha Kanwal, Hashem B El-Serag, Joseph F Petrosino, Li Jiao

Faculty, Staff and Students Publications

A high-fat diet has been associated with systemic diseases in humans and alterations in gut microbiota in animal studies. However, the influence of dietary fatty acid intake on gut microbiota in humans has not been well studied. In this cross-sectional study, we examined the association between intake of total fatty acids (TFAs), saturated fatty acids (SFAs), trans fatty acids (TrFAs), monounsaturated fatty acids (MUFAs), polyunsaturated fatty acids (PUFAs), n3-FAs, and n6-FAs, and the community composition and structure of the adherent colonic gut microbiota. We obtained 97 colonic biopsies from 34 participants with endoscopically normal colons. Microbial DNA was used to …