Microbiology Commons^™

Assessment Of The Cytolytic Potential Of A Multivirus-Targeted T Cell Therapy Using A Vital Dye-Based, Flow Cytometric Assay, Kiriakos Koukoulias, Penelope G Papayanni, Julia Jones, Manik Kuvalekar, Ayumi Watanabe, Yovana Velazquez, Sarah Gilmore, Anastasia Papadopoulou, Ann M Leen, Spyridoula Vasileiou

Faculty, Staff and Students Publications

Reliable and sensitive characterization assays are important determinants of the successful clinical translation of immunotherapies. For the assessment of cytolytic potential, the chromium 51 (51Cr) release assay has long been considered the gold standard for testing effector cells. However, attaining the approvals to access and use radioactive isotopes is becoming increasingly complex, while technical aspects [i.e. sensitivity, short (4-6 hours) assay duration] may lead to suboptimal performance. This has been the case with our ex vivo expanded, polyclonal (CD4+ and CD8+) multivirus-specific T cell (multiVST) lines, which recognize 5 difficult-to-treat viruses [Adenovirus (AdV), BK virus (BKV), cytomegalovirus (CMV), Epstein Barr …

Editorial: Health Effects And Pathophysiological Mechanisms Of One-Carbon Metabolism Nutrients Intake Throughout The Life Cycle, Jufen Liu, Yunping Lei, Lei Wang, Chao Guo

Faculty, Staff and Students Publications

No abstract provided.

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 …

The Small Intestinal Microbiome: Vibing With Intestinal Stem Cells, Victoria Poplaski, Faith Sawyer, Sarah E Blutt

Faculty, Staff and Students Publications

The epithelial lining of the small intestine mediates its absorptive and secretory function and thus is a critical component of human health. Regeneration and renewal of the epithelium is the result of proliferation of intestinal stem cells (ISCs). Many cell types and molecular factors are known to regulate the ability of ISCs to proliferate, including adjacent neighboring epithelial cells and the underlying, supportive stromal cells. The microbiome resides in the lumen of the small intestine and is in close contact with the epithelium. Due to its proximity to ISCs, it has been hypothesized that species within the microbiome have the …

Gene-Environment Interactions Underlying The Etiology Of Neural Tube Defects, Carlo Donato Caiaffa, Cristiane Sá Roriz Fonteles, Lei Yunping, Richard H Finnell

Faculty, Staff and Students Publications

Neural tube defects (NTDs) consist of severe structural malformations of the brain and spinal cord and are the second most common structural birth defect in humans, accounting for approximately 2700 affected pregnancies every year in the United States. These numbers are highly significant, considering that birth defects remain a leading cause of infant mortality in the United States, affecting approximately 120,000 babies born annually. Survivors of these congenital malformations face long-term disability and lifelong challenges imposed by severe physical burdens compromising the afflicted individual's overall quality of life. Clearly, birth defects, and especially NTDs remain a global public health challenge, …

Toward More Rigorous And Informative Nutritional Epidemiology: The Rational Space Between Dismissal And Defense Of The Status Quo, Andrew W Brown, Stella Aslibekyan, Dennis Bier, Rafael Ferreira Da Silva, Adam Hoover, David M Klurfeld, Eric Loken, Evan Mayo-Wilson, Nir Menachemi, Greg Pavela, Patrick D Quinn, Dale Schoeller, Carmen Tekwe, Danny Valdez, Colby J Vorland, Leah D Whigham, David B Allison

Faculty, Staff and Students Publications

To date, nutritional epidemiology has relied heavily on relatively weak methods including simple observational designs and substandard measurements. Despite low internal validity and other sources of bias, claims of causality are made commonly in this literature. Nutritional epidemiology investigations can be improved through greater scientific rigor and adherence to scientific reporting commensurate with research methods used. Some commentators advocate jettisoning nutritional epidemiology entirely, perhaps believing improvements are impossible. Still others support only normative refinements. But neither abolition nor minor tweaks are appropriate. Nutritional epidemiology, in its present state, offers utility, yet also needs marked, reformational renovation. Changing the status quo …

Super-Enhanced Marco Variant Drives Triple-Negative Breast Cancer Progression, Weei-Chin Lin, Fang-Tsyr Lin

Faculty, Staff and Students Publications

No abstract provided.

Place Cells Dynamically Refine Grid Cell Activities To Reduce Error Accumulation During Path Integration In A Continuous Attractor Model, Jose A Fernandez-Leon, Ahmet Kerim Uysal, Daoyun Ji

Faculty, Staff and Students Publications

Navigation is one of the most fundamental skills of animals. During spatial navigation, grid cells in the medial entorhinal cortex process speed and direction of the animal to map the environment. Hippocampal place cells, in turn, encode place using sensory signals and reduce the accumulated error of grid cells for path integration. Although both cell types are part of the path integration system, the dynamic relationship between place and grid cells and the error reduction mechanism is yet to be understood. We implemented a realistic model of grid cells based on a continuous attractor model. The grid cell model was …

Activity Disruption Causes Degeneration Of Entorhinal Neurons In A Mouse Model Of Alzheimer’S Circuit Dysfunction, Rong Zhao, Stacy D Grunke, Caleb A Wood, Gabriella A Perez, Melissa Comstock, Ming-Hua Li, Anand K Singh, Kyung-Won Park, Joanna L Jankowsky

Faculty, Staff and Students Publications

Neurodegenerative diseases are characterized by selective vulnerability of distinct cell populations; however, the cause for this specificity remains elusive. Here, we show that entorhinal cortex layer 2 (EC2) neurons are unusually vulnerable to prolonged neuronal inactivity compared with neighboring regions of the temporal lobe, and that reelin + stellate cells connecting EC with the hippocampus are preferentially susceptible within the EC2 population. We demonstrate that neuronal death after silencing can be elicited through multiple independent means of activity inhibition, and that preventing synaptic release, either alone or in combination with electrical shunting, is sufficient to elicit silencing-induced degeneration. Finally, we …

Loss Of Wnt4 In The Gubernaculum Causes Unilateral Cryptorchidism And Fertility Defects, Abhishek Seth, Juan C Bournat, Olga Medina-Martinez, Armando Rivera, Joshua Moore, Hunter Flores, Jill A Rosenfeld, Liya Hu, Carolina J Jorgez

Faculty, Staff and Students Publications

Undescended testis (UDT) affects 6% of male births. Despite surgical correction, some men with unilateral UDT may experience infertility with the contralateral descended testis (CDT) showing no A-dark spermatogonia. To improve our understanding of the etiology of infertility in UDT, we generated a novel murine model of left unilateral UDT. Gubernaculum-specific Wnt4 knockout (KO) mice (Wnt4-cKO) were generated using retinoic acid receptor β2-cre mice and were found to have a smaller left-unilateral UDT. Wnt4-cKO mice with abdominal UDT had an increase in serum follicle-stimulating hormone and luteinizing hormone and an absence of germ cells in the undescended testicle. Wnt4-cKO mice …

Human Islet Amyloid Polypeptide (Hiapp) Protofibril-Specific Antibodies For Detection And Treatment Of Type 2 Diabetes, Angelina S Bortoletto, W Vallen Graham, Gabriella Trout, Alessandra Bonito-Oliva, Manija A Kazmi, Jing Gong, Emily Weyburne, Brandy L Houser, Thomas P Sakmar, Ronald J Parchem

Faculty, Staff and Students Publications

Type 2 diabetes mellitus (T2D) is a major public health concern and is characterized by sustained hyperglycemia due to insulin resistance and destruction of insulin-producing β cells. One pathological hallmark of T2D is the toxic accumulation of human islet amyloid polypeptide (hIAPP) aggregates. Monomeric hIAPP is a hormone normally co-secreted with insulin. However, increased levels of hIAPP in prediabetic and diabetic patients can lead to the formation of hIAPP protofibrils, which are toxic to β cells. Current therapies fail to address hIAPP aggregation and current screening modalities do not detect it. Using a stabilizing capping protein, monoclonal antibodies (mAbs) can …

Chronic Kidney Disease, Risk Of Readmission, And Progression To End-Stage Renal Disease In 519,387 Patients Undergoing Coronary Artery Bypass Grafting, Ryan Nowrouzi, Christopher B Sylvester, John A Treffalls, Qianzi Zhang, Todd K Rosengart, Joseph S Coselli, Marc R Moon, Ravi K Ghanta, Subhasis Chatterjee

Faculty, Staff and Students Publications

Objective: The association between chronic kidney disease and adverse outcomes after coronary artery bypass grafting is well established; in contrast, the association between chronic kidney disease and readmission has been less thoroughly investigated. We hypothesized that patients at higher chronic kidney disease stages have greater risk of readmission, poorer operative outcomes, and greater hospitalization cost.

Methods: Using the 2016-2018 Nationwide Readmissions Database, we identified 519,387 patients who underwent isolated coronary artery bypass grafting. Patients were stratified by chronic kidney disease stage based on International Classification of Diseases 10th Revision classification. Multivariable logistic regression was used to assess risk factors for …

Effects Of Α And Β-Adrenergic Signaling On Innate Immunity And Porphyromonas Gingivalis Virulence In An Invertebrate Model, Renata Mendonça Moraes, Maíra Terra Garcia, Fabio Stossi, Patrícia Pimentel De Barros, Juliana Campos Junqueira, Ana Lia Anbinder

Faculty, Staff and Students Publications

To investigate the role of adrenergic signalling (AS) in the host immune response and Porphyromonas gingivalis virulence, we compared norepinephrine (NE) and isoproterenol (ISO) responses in Galleria mellonella. P. gingivalis infection was evaluated by survival; humoral immune responses (i.e. melanization and cecropin and gloverin mRNA expression); cellular immune responses (i.e. haemocyte count, nodulation by histology); and P. gingivalis recovery (CFU/mL). P. gingivalis was cultivated in the presence of ISO (PgISO) or NE and injected into the larvae for survival evaluation. Finally, we co-injected ISO and PgISO to evaluate the concomitant effects on the immune response and bacterial virulence. None …

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 …

Successful Use Of Continuous Erector Spinae Plane Blocks In A Patient With Variant Angina After Large Ventral Hernia Repair, Alexandra L Belfar, Yi Deng, Raymond C Yu, Annas Sabbagh

Faculty, Staff and Students Publications

Coronary artery spasm constitutes the primary underlying pathology of variant angina. Because provocation of coronary artery spasm may occur with both excess sympathetic and excess parasympathetic stimulation, patients with this disorder have extremely limited options for perioperative pain control. This is especially true for procedures involving extensive abdominal incision/manipulation. Whereas neuraxial analgesia might otherwise be appropriate in these cases, several studies have demonstrated that coronary artery spasm can occur as a result of epidural placement, and therefore, that this may not be an optimal choice for patients with variant angina. This report discusses the case of a patient with a …

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 …

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, …

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 …

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 …

Temporal Changes In Gastrointestinal Fungi And The Risk Of Autoimmunity During Early Childhood: The Teddy Study, Thomas A Auchtung, Christopher J Stewart, Daniel P Smith, Eric W Triplett, Daniel Agardh, William A Hagopian, Anette G Ziegler, Marian J Rewers, Jin-Xiong She, Jorma Toppari, Åke Lernmark, Beena Akolkar, Jeffrey P Krischer, Kendra Vehik, Jennifer M Auchtung, Nadim J Ajami, Joseph F Petrosino

Faculty, Staff and Students Publications

Fungal infections are a major health problem that often begin in the gastrointestinal tract. Gut microbe interactions in early childhood are critical for proper immune responses, yet there is little known about the development of the fungal population from infancy into childhood. Here, as part of the TEDDY (The Environmental Determinants of Diabetes in the Young) study, we examine stool samples of 888 children from 3 to 48 months and find considerable differences between fungi and bacteria. The metagenomic relative abundance of fungi was extremely low but increased while weaning from milk and formula. Overall fungal diversity remained constant over …

Discovery Of The First Lyticstaphylococcus Pseudintermedius/ Staphylococcus Aureus Polyvalent Bacteriophages, Haroldo Hernandez Santos, Justin Clark, Austen Terwilliger, Anthony Maresso

Faculty, Staff and Students Publications

Background:

There are no verified lytic Staphylococcus pseudintermedius phages in the literature and few temperate phage genomes in databases. S. pseudintermedius is an opportunistic zoonotic pathogen of great importance in veterinary and human medicine.

Materials and Methods:

We discovered phages against canine-derived S. pseudintermedius isolates by screening dog feces, hair, and skin swabs. Fourteen new phages were isolated and characterized by genomic analysis, transmission electron microscopy, and host range determination.

Results:

Three phages—DH2, DH5, and DS10, a phage K variant—were predicted lytic by sequencing, a designation supported by mitomycin C induction. All three are S. pseudintermedius and Staphylococcus aureus polyvalent …

Systems Biology Approach To Functionally Assess The Clostridioides Difficile Pangenome Reveals Genetic Diversity With Discriminatory Power, Charles J Norsigian, Heather A Danhof, Colleen K Brand, Firas S Midani, Jared T Broddrick, Tor C Savidge, Robert A Britton, Bernhard O Palsson, Jennifer K Spinler, Jonathan M Monk

Faculty, Staff and Students Publications

Combatting Clostridioides difficile infections, a dominant cause of hospital-associated infections with incidence and resulting deaths increasing worldwide, is complicated by the frequent emergence of new virulent strains. Here, we employ whole-genome sequencing, high-throughput phenotypic screenings, and genome-scale models of metabolism to evaluate the genetic diversity of 451 strains of C. difficile. Constructing the C. difficile pangenome based on this set revealed 9,924 distinct gene clusters, of which 2,899 (29%) are defined as core, 2,968 (30%) are defined as unique, and the remaining 4,057 (41%) are defined as accessory. We develop a strain typing method, sequence typing by accessory genome (STAG), …

Roles Of Small Rnas And Paralogous Proteins In Bacillus Anthracis Virulence Gene Regulation, Ileana Corsi

Dissertations and Theses (Open Access)

Bacteria have evolved a myriad of regulatory mechanisms to control gene expression. One of the most common mechanisms is post-transcriptional control through the function of small regulatory RNAs (sRNAs). Small regulatory RNAs (sRNAs) are short transcripts that base-pair to mRNA targets or interact with regulatory proteins. sRNA function has been studied extensively in Gram-negative bacteria; comparatively less is known about sRNAs in Firmicutes. In this dissertation, I investigated two sRNAs encoded within the virulence plasmid pXO1 of Bacillus anthracis, the causative agent of anthrax. The sRNAs, named “XrrA and XrrB” (for p­XO1-encoded regulatory RNA) are abundant and highly stable …