Medical Microbiology Commons^™

A Mutation In F-Actin Polymerization Factor Suppresses The Distal Arthrogryposis Type 5 Piezo2 Pathogenic Variant In Caenorhabditis Elegans, Xiaofei Bai, Harold E Smith, Luis O Romero, Briar Bell, Valeria Vásquez, Andy Golden

Faculty, Staff and Student Publications

The mechanosensitive PIEZO channel family has been linked to over 26 disorders and diseases. Although progress has been made in understanding these channels at the structural and functional levels, the underlying mechanisms of PIEZO-associated diseases remain elusive. In this study, we engineered four PIEZO-based disease models using CRISPR/Cas9 gene editing. We performed an unbiased chemical mutagen-based genetic suppressor screen to identify putative suppressors of a conserved gain-of-function variant pezo-1[R2405P] that in human PIEZO2 causes distal arthrogryposis type 5 (DA5; p. R2718P). Electrophysiological analyses indicate that pezo-1(R2405P) is a gain-of-function allele. Using genomic mapping and whole-genome sequencing approaches, we identified a …

Oral Microbiome Associated With Differential Ratios Of Porphyromonas Gingivalis And Streptococcus Cristatus, Qingguo Wang, Bing-Yan Wang, Siddharth Pratap, Hua Xie

Faculty, Staff and Student Publications

Periodontitis has recently been defined as a dysbiotic disease caused by an imbalanced oral microbiota. The transition from commensal microbial communities to periodontitis-associated ones requires colonization by specific pathogens, including Porphyromonas gingivalis. We previously reported an antagonistic relationship between Streptococcus cristatus and P. gingivalis. To determine the role of S. cristatus in altering the interactions of P. gingivalis with other oral bacteria in a complex context, we collected dental plaque samples from patients with periodontitis and assigned them to two groups based on the ratios of S. cristatus and P. gingivalis. We then characterized the microbial profiles …

Metabolic Model Predictions Enable Targeted Microbiome Manipulation Through Precision Prebiotics, Georgios Marinos, Inga K Hamerich, Reena Debray, Nancy Obeng, Carola Petersen, Jan Taubenheim, Johannes Zimmermann, Dana Blackburn, Buck S Samuel, Katja Dierking, Andre Franke, Matthias Laudes, Silvio Waschina, Hinrich Schulenburg, Christoph Kaleta

Faculty, Staff and Students Publications

While numerous health-beneficial interactions between host and microbiota have been identified, there is still a lack of targeted approaches for modulating these interactions. Thus, we here identify precision prebiotics that specifically modulate the abundance of a microbiome member species of interest. In the first step, we show that defining precision prebiotics by compounds that are only taken up by the target species but no other species in a community is usually not possible due to overlapping metabolic niches. Subsequently, we use metabolic modeling to identify precision prebiotics for a two-member Caenorhabditis elegans microbiome community comprising the immune-protective target species Pseudomonas …

Respiratory Viral Detection In The Plasma And Cerebrospinal Fluid (Csf) Of Young Febrile Infants, Erin G Nicholson, Vasanthi Avadhanula, Leila C Sahni, Laura Ferlic-Stark, Lauren Maurer, Julie A Boom, Pedro A Piedra

Faculty, Staff and Students Publications

BACKGROUND: Respiratory viral infections are common in febrile infants ≤90 days. However, the detection of viruses other than enterovirus in the blood and cerebrospinal fluid (CSF) of young infants is not well defined. We sought to quantify the occurrence of respiratory viruses in the blood and CSF of febrile infants ≤90 days.

METHODS: We conducted a nested cohort study examining plasma and CSF samples from febrile infants 15-90 days via rtPCR. The samples were tested for respiratory viruses (respiratory syncytial virus, influenza, enterovirus, parechovirus, adenovirus, bocavirus). Clinical and laboratory data were also collected to determine the presence of serious bacterial …

Important Features For Protein Foldings In Two Acyl Carrier Proteins From Enterococcus Faecalis, Seoyeong Yoo, Jiwon Yeon, Eunhee Kim, Yangmee Kim

Faculty, Staff and Student Publications

The emergence of multi-drug resistant Enterococcus faecalis raises a serious threat to global public health. E. faecalis is a gram-positive intestinal commensal bacterium found in humans. E. faecalis can endure extreme environments such as high temperature, pressure, and high salt, which facilitates them to cause infection in hospitals. E. faecalis has two acyl carrier proteins, AcpA (EfAcpA) in de novo fatty acid synthesis (FAS) and AcpB (EfAcpB) which utilizes exogenous fatty acids. Previously, we determined the tertiary structures of these two ACPs and investigated their structure-function relationships. Solution structures revealed that overall folding of these two ACPs is similar to …

Comparison Of Three Rapid Diagnostic Tests For Bloodstream Infections Using Benefit-Risk Evaluation Framework (Bed-Frame), Richard D Smith, Min Zhan, Shanshan Zhang, Surbhi Leekha, Anthony Harris, Yohei Doi, Scott Evans, J Kristie Johnson, Robert K Ernst

Faculty, Staff and Student Publications

Rapid diagnostic tests (RDTs) for bloodstream infections have the potential to reduce time to appropriate antimicrobial therapy and improve patient outcomes. Previously, an in-house, lipid-based, matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) method, Fast Lipid Analysis Technique (FLAT MS), has shown promise as a rapid pathogen identification method. In this study, FLAT MS for direct from blood culture identification was evaluated and compared to FDA-cleared identification methods using the Benefit-risk Evaluation Framework (BED-FRAME) analysis. FLAT MS was evaluated and compared to Bruker Sepsityper and bioMérieux BioFire FilmArray BCID2 using results from a previous study. For this study, 301 …

Fbpp: Software To Design Pcr Primers And Probes For Nucleic Acid Base Detection Of Foodborne Pathogens, Mohamed A Soliman, Mohamed S Azab, Hala A Hussein, Mohamed M Roushdy, Mohamed N Abu El-Naga

Faculty, Staff and Student Publications

Foodborne pathogens can be found in various foods, and it is important to detect foodborne pathogens to provide a safe food supply and to prevent foodborne diseases. The nucleic acid base detection method is one of the most rapid and widely used methods in the detection of foodborne pathogens; it depends on hybridizing the target nucleic acid sequence to a synthetic oligonucleotide (probes or primers) that is complementary to the target sequence. Designing primers and probes for this method is a preliminary and critical step. However, new bioinformatics tools are needed to automate, specific and improve the design sets to …

Gut Epithelial Interleukin-17 Receptor A Signaling Can Modulate Distant Tumors Growth Through Microbial Regulation, Vidhi Chandra, Le Li, Olivereen Le Roux, Yu Zhang, Rian M Howell, Dhwani N Rupani, Seyda Baydogan, Haiyan D Miller, Erick Riquelme, Joseph Petrosino, Michael P Kim, Krishna P L Bhat, James R White, Jay K Kolls, Yuliya Pylayeva-Gupta, Florencia Mcallister

Faculty, Staff and Student Publications

Microbes influence cancer initiation, progression and therapy responsiveness. IL-17 signaling contributes to gut barrier immunity by regulating microbes but also drives tumor growth. A knowledge gap remains regarding the influence of enteric IL-17-IL-17RA signaling and their microbial regulation on the behavior of distant tumors. We demonstrate that gut dysbiosis induced by systemic or gut epithelial deletion of IL-17RA induces growth of pancreatic and brain tumors due to excessive development of Th17, primary source of IL-17 in human and mouse pancreatic ductal adenocarcinoma, as well as B cells that circulate to distant tumors. Microbial dependent IL-17 signaling increases DUOX2 signaling in …

Preclinical Repurposing Of Sitagliptin As A Drug Candidate For Colorectal Cancer By Targeting Cd24/Ctnnb1/Sox4-Centered Signaling Hub, Jing-Wen Shih, Alexander T H Wu, Ntlotlang Mokgautsi, Po-Li Wei, Yan-Jiun Huang

Faculty, Staff and Student Publications

Despite significant advances in treatment modalities, colorectal cancer (CRC) remains a poorly understood and highly lethal malignancy worldwide. Cancer stem cells (CSCs) and the tumor microenvironment (TME) have been shown to play critical roles in initiating and promoting CRC progression, metastasis, and treatment resistance. Therefore, a better understanding of the underlying mechanisms contributing to the generation and maintenance of CSCs is crucial to developing CSC-specific therapeutics and improving the current standard of care for CRC patients. To this end, we used a bioinformatics approach to identify increased CD24/SOX4 expression in CRC samples associated with poor prognosis. We also …

Metabolism Shapes Immune Responses To Staphylococcus Aureus., Prabhakar Arumugam, Tammy Kielian

Journal Articles: Pathology and Microbiology

BACKGROUND: Staphylococcus aureus (S. aureus) is a common cause of hospital- and community-acquired infections that can result in various clinical manifestations ranging from mild to severe disease. The bacterium utilizes different combinations of virulence factors and biofilm formation to establish a successful infection, and the emergence of methicillin- and vancomycin-resistant strains introduces additional challenges for infection management and treatment.

SUMMARY: Metabolic programming of immune cells regulates the balance of energy requirements for activation and dictates pro- versus anti-inflammatory function. Recent investigations into metabolic adaptations of leukocytes and S. aureus during infection indicate that metabolic crosstalk plays a crucial role in …

Bacterial Single-Cell Rna Sequencing Captures Biofilm Transcriptional Heterogeneity And Differential Responses To Immune Pressure, Lee E. Korshoj, Tammy Kielian

Journal Articles: Pathology and Microbiology

Biofilm formation is an important mechanism of survival and persistence for many bacterial pathogens. These multicellular communities contain subpopulations of cells that display metabolic and transcriptional diversity along with recalcitrance to antibiotics and host immune defenses. Here, we present an optimized bacterial single-cell RNA sequencing method, BaSSSh-seq, to study Staphylococcus aureus diversity during biofilm growth and transcriptional adaptations following immune cell exposure. BaSSSh-seq captures extensive transcriptional heterogeneity during biofilm compared to planktonic growth. We quantify and visualize transcriptional regulatory networks across heterogeneous biofilm subpopulations and identify gene sets that are associated with a trajectory from planktonic to biofilm growth. BaSSSh-seq …

Metabolic Diversity Of Human Macrophages: Potential Influence On Staphylococcus Aureus Intracellular Survival, Blake P. Bertrand, Dhananjay Shinde, Vinai C. Thomas, Marvin Whiteley, Carolyn B. Ibberson, Tammy Kielian

Journal Articles: Pathology and Microbiology

Staphylococcus aureus is a leading cause of medical device-associated biofilm infections. This is influenced by the ability of S. aureus biofilm to evade the host immune response, which is partially driven by the anti-inflammatory cytokine interleukin-10 (IL-10). Here, we show that treatment of human monocyte-derived macrophages (HMDMs) with IL-10 enhanced biofilm formation, suggesting that macrophage anti-inflammatory programming likely plays an important role during the transition from planktonic to biofilm growth. To identify S. aureus genes that were important for intracellular survival in HMDMs and how this was affected by IL-10, transposon sequencing was performed. The size of the S. aureus …

Tetracycline And Oxacillin Act Synergistically On Biofilms And Display Increased Efficacy In Vivo Against Staphylococcus Aureus, Amy K. Tooke, Rebecca E. Hodges, Josie F. Pyrah, Kenneth W. Bayles, Stephen A. Renshaw, Simon J. Foster

Journal Articles: Pathology and Microbiology

Oxacillin (bactericidal) and tetracycline (bacteriostatic) are clinically relevant antibiotics that are routinely prescribed to treat Staphylococcus aureus infections but not conventionally used in combination. There is an urgent need for treatment regimens that can act upon biofilms during infection, associated with chronic infections on indwelling devices, as well as acute planktonic (systemic) infection. Here we show that in an in vitro model oxacillin and tetracycline act synergistically against S. aureus UAMS-1 biofilms, reducing the concentration of both antibiotics necessary to eradicate an established biofilm. Using an in vivo zebrafish larval infection model with S. aureus NewHG, they display improved bacterial …

Potential Prognostic Determinants For Fet::Creb Fusion-Positive Intracranial Mesenchymal Tumor, Frank M. Mezzacappa, Frankie K. Smith, Weiwei Zhang, Andrew Gard, Fatmagul Kusku Cabuk, Ignancio Gonzalez-Gomez, Hector L. Monforte, Jiancong Liang, Omkar Singh, Martha M. Quezado, Kenneth D. Aldape, Murat Gokden, Julia A. Bridge, Jie Chen

Journal Articles: Pathology and Microbiology

Intracranial mesenchymal tumor (IMT), FET::CREB fusion-positive is a provisional tumor type in the 2021 WHO classification of central nervous system tumors with limited information available. Herein, we describe five new IMT cases from four females and one male with three harboring an EWSR1::CREM fusion and two featuring an EWSR1::ATF1 fusion. Uniform manifold approximation and projection of DNA methylation array data placed two cases to the methylation class "IMT, subclass B", one to "meningioma-benign" and one to "meningioma-intermediate". A literature review identified 74 cases of IMTs (current five cases included) with a median age of 23 years (range 4-79 years) and …

Synergistic Effects Of Antimicrobial Components Of The Human-Derived Composite Amnion-Chorion Membrane On Bacterial Growth, Alexandra Su Brummerhop, Chun-Teh Lee, Robin Weltman, Gena D Tribble, Ransome Van Der Hoeven, Yulun Chiu, Jianming Hong, Bing-Yan Wang

Faculty, Staff and Student Publications

Introduction: The human-derived amnion-chorion membrane (ACM) has endogenous antimicrobial properties, which are important for preventing the colonization and survival of oral bacteria on exposed membranes. This project aimed to decipher the underlying mechanism by identifying the components of ACM that confer antibacterial properties. In addition, the antimicrobial efficacy of these identified components on oral bacteria was assessed.

Methods: Four antimicrobial proteins, histone H2A/H2B, cathelicidin LL-37, lactoferrin, and lysozyme, were identified via mass spectrometry in ACM. These proteins were then assessed for their efficacy in killing Streptococcus gordonii Challis. Log-phased bacterial cells were cultured with the commercially available proteins that were …

Persistent Microbial Infections And Idiopathic Pulmonary Fibrosis – An Insight Into Non-Typeable Haemophilus Influenza Pathogenesis, Anthony Shadid, Haydn E Rich, Hunter Devaughn, Aleksey Domozhirov, Marie-Françoise Doursout, Tingting Weng-Mills, Kristin L Eckel-Mahan, Harry Karmouty-Quintana, Marcos I Restrepo, Pooja Shivshankar

Faculty, Staff and Student Publications

Interstitial lung disease (ILD) is characterized by chronic inflammation and scarring of the lungs, of which idiopathic pulmonary fibrosis (IPF) is the most devastating pathologic form. Idiopathic pulmonary fibrosis pathogenesis leads to loss of lung function and eventual death in 50% of patients, making it the leading cause of ILD-associated mortality worldwide. Persistent and subclinical microbial infections are implicated in the acute exacerbation of chronic lung diseases. However, while epidemiological studies have highlighted pollutants, gastric aspirate, and microbial infections as major causes for the progression and exacerbation of IPF, the role of persistent microbial infections in the pathogenesis of IPF …

Effects And Plasma Proteomic Analysis Of Glp-1ra Versus Cpa/Ee, In Combination With Metformin, On Overweight Pcos Women: A Randomized Controlled Trial, Mingyu Liao, Xing Li, Hao Zhang, Ling Zhou, Liu Shi, Weixin Li, Rufei Shen, Guiliang Peng, Huan Zhao, Jiaqing Shao, Xiujie Wang, Zheng Sun, Hongting Zheng, Min Long

Faculty, Staff and Students Publications

PURPOSE: Polycystic ovary syndrome (PCOS) is characterized by reproductive dysfunctions and metabolic disorders. This study aims to compare the therapeutic effectiveness of glucagon-like peptide-1 receptor agonist (GLP-1RA) + Metformin (Met) versus cyproterone acetate/ethinylestradiol (CPA/EE) + Met in overweight PCOS women and identify potential proteomic biomarkers of disease risk in women with PCOS.

METHODS: In this prospective, open-label randomized controlled trial, we recruited 60 overweight PCOS women into two groups at a 1:1 ratio to receive CPA/EE (2 mg/day: 2 mg cyproterone acetate and 35-μg ethinylestradiol,) +Met (1500 mg/day) or GLP-1 RA (liraglutide, 1.2-1.8 mg/day) +Met (1500 mg/day) for 12 weeks. …

Prospective Associations Of Psychedelic Treatment For Co-Occurring Alcohol Misuse And Posttraumatic Stress Symptoms Among United States Special Operations Forces Veterans, Stacey B Armstrong, Yitong Xin, Nathan D Sepeda, Martín Polanco, Lynnette A Averill, Alan K Davis

Faculty, Staff and Students Publications

This study evaluated prospective associations of ibogaine and 5-MeO-DMT treatment for risky alcohol use and post-traumatic stress disorder (PTSD) symptoms among United States (US) Special Operations Forces Veterans (SOFV). Data were collected during standard clinical operations at pre-treatment and 1-month (1 m), 3-months (3 m), and 6-months (6 m) post-treatment in an ibogaine and 5-MeO-DMT treatment program in Mexico. Of the 86 SOFV that completed treatment, 45 met criteria for risky alcohol use at pre-treatment (mean age = 44; male = 100%; White = 91%). There was a significant reduction in alcohol use from pre-treatment (M = 7.2, SD = …

A Novel System To Culture Human Intestinal Organoids Under Physiological Oxygen Content To Study Microbial-Host Interaction, Tatiana Y Fofanova, Umesh C Karandikar, Jennifer M Auchtung, Reid L Wilson, Antonio J Valentin, Robert A Britton, K Jane Grande-Allen, Mary K Estes, Kristi Hoffman, Sashirekha Ramani, Christopher J Stewart, Joseph F Petrosino

Faculty, Staff and Students Publications

Mechanistic investigation of host-microbe interactions in the human gut are hindered by difficulty of co-culturing microbes with intestinal epithelial cells. On one hand the gut bacteria are a mix of facultative, aerotolerant or obligate anaerobes, while the intestinal epithelium requires oxygen for growth and function. Thus, a coculture system that can recreate these contrasting oxygen requirements is critical step towards our understanding microbial-host interactions in the human gut. Here, we demonstrate Intestinal Organoid Physoxic Coculture (IOPC) system, a simple and cost-effective method for coculturing anaerobic intestinal bacteria with human intestinal organoids (HIOs). Using commensal anaerobes with varying degrees of oxygen …

Traf4-Mediated Nonproteolytic Ubiquitination Of Androgen Receptor Promotes Castration-Resistant Prostate Cancer, Yosi Gilad, Ortal Shimon, Sang Jun Han, David M Lonard, Bert W O'Malley

Faculty, Staff and Students Publications

Steroid receptor coactivators (SRCs) are master regulators of transcription that play key roles in human physiology and pathology. SRCs are particularly important for the regulation of the immune system with major roles in lymphocyte fate determination and function, macrophage activity, regulation of nuclear factor κB (NF-κB) transcriptional activity and other immune system biology. The three members of the p160 SRC family comprise a network of immune-regulatory proteins that can function independently or act in synergy with each other, and compensate for - or moderate - the activity of other SRCs. Recent evidence indicates that the SRCs are key participants in …

Vaccines Against Extraintestinal Pathogenic Escherichia Coli (Expec): Progress And Challenges, Ling Qiu, Dylan Chirman, Justin R Clark, Yikun Xing, Haroldo Hernandez Santos, Ellen E Vaughan, Anthony W Maresso

Faculty, Staff and Students Publications

The emergence of antimicrobial resistance (AMR) is a principal global health crisis projected to cause 10 million deaths annually worldwide by 2050. While the Gram-negative bacteria Escherichia coli is commonly found as a commensal microbe in the human gut, some strains are dangerously pathogenic, contributing to the highest AMR-associated mortality. Strains of E. coli that can translocate from the gastrointestinal tract to distal sites, called extraintestinal E. coli (ExPEC), are particularly problematic and predominantly afflict women, the elderly, and immunocompromised populations. Despite nearly 40 years of clinical trials, there is still no vaccine against ExPEC. One reason for this is …

Select Gut Microbiota Impede Rotavirus Vaccine Efficacy, Vu L Ngo, Yanling Wang, Yadong Wang, Zhenda Shi, Robert Britton, Jun Zou, Sasirekha Ramani, Baoming Jiang, Andrew T Gewirtz

Faculty, Staff and Students Publications

BACKGROUND & AIMS: The protection provided by rotavirus (RV) vaccines is highly heterogeneous among individuals. We hypothesized that microbiota composition might influence RV vaccine efficacy.

METHODS: First, we examined the potential of segmented filamentous bacteria (SFB) colonization to influence RV vaccine efficacy in mice. Next, we probed the influence of human microbiomes on RV vaccination via administering mice fecal microbial transplants (FMTs) from children with robust or minimal RV vaccine responsiveness. Post-FMT, mice were subjected to RV vaccination followed by RV challenge.

RESULTS: SFB colonization induced a phenotype that was reminiscent of RV vaccine failure (ie, failure to generate RV …

Spatial Transcriptomics Resolve An Emphysema-Specific Lymphoid Follicle B Cell Signature In Chronic Obstructive Pulmonary Disease, Joselyn Rojas-Quintero, Scott A Ochsner, Felicia New, Prajan Divakar, Chen Xi Yang, Tianshi David Wu, Jerid Robinson, Darshan Shimoga Chandrashekar, Nicholas E Banovich, Ivan O Rosas, Maor Sauler, Farrah Kheradmand, Amit Gaggar, Camilla Margaroli, Raul San Jose Estepar, Neil J Mckenna, Francesca Polverino

Faculty, Staff and Students Publications

Rationale

Within chronic obstructive pulmonary disease (COPD), emphysema is characterized by a significant yet partially understood B cell immune component.

Objectives

To characterize the transcriptomic signatures from lymphoid follicles (LFs) in ever-smokers without COPD and patients with COPD with varying degrees of emphysema.

Methods

Lung sections from 40 patients with COPD and ever-smokers were used for LF proteomic and transcriptomic spatial profiling. Formalin- and O.C.T.-fixed lung samples obtained from biopsies or lung explants were assessed for LF presence. Emphysema measurements were obtained from clinical chest computed tomographic scans. High-confidence transcriptional target intersection analyses were conducted to resolve emphysema-induced transcriptional networks. …

Triobp Modulates Β-Catenin Signaling By Regulation Of Mir-29b In Idiopathic Pulmonary Fibrosis, Lan Wang, Wenyu Zhao, Cong Xia, Shuaichen Ma, Zhongzheng Li, Ningdan Wang, Linke Ding, Yaxuan Wang, Lianhui Cheng, Huibing Liu, Juntang Yang, Yajun Li, Ivan Rosas, Guoying Yu

Faculty, Staff and Students Publications

Idiopathic pulmonary fibrosis (IPF) is a fatal and devastating lung disease of unknown etiology, described as the result of multiple cycles of epithelial cell injury and fibroblast activation. Despite this impressive increase in understanding, a therapy that reverses this form of fibrosis remains elusive. In our previous study, we found that miR-29b has a therapeutic effect on pulmonary fibrosis. However, its anti-fibrotic mechanism is not yet clear. Recently, our study identified that F-Actin Binding Protein (TRIOBP) is one of the target genes of miR-29b and found that deficiency of TRIOBP increases resistance to lung fibrosis in vivo. TRIOBP knockdown inhibited …

The Potential For Development Of Clinically Relevant Microbial Resistance To Rifaximin-Α: A Narrative Review, Herbert L Dupont

Faculty, Staff and Student Publications

Rifaximin-α is a gut-targeted antibiotic indicated for numerous gastrointestinal and liver diseases. Its multifaceted mechanism of action goes beyond direct antimicrobial effects, including alterations in bacterial virulence, cytoprotective effects on host epithelial cells, improvement of impaired intestinal permeability, and reduction of proinflammatory cytokine expression via activation of the pregnane X receptor. Rifaximin-α is virtually non-absorbed, with low systemic drug levels contributing to its excellent safety profile. While there are high concentrations of drug in the colon, low water solubility leads to low colonic drug bioavailability, protecting the gut microbiome. Rifaximin-α appears to be more active in the bile-rich small bowel. …

Bacterial Outer Membrane Vesicles Provide An Alternative Pathway For Trafficking Of Escherichia Coli O157 Type Iii Secreted Effectors To Epithelial Cells, Natalie Sirisaengtaksin, Eloise J O'Donoghue, Sara Jabbari, Andrew J Roe, Anne Marie Krachler

Faculty, Staff and Student Publications

Outer membrane vesicles (OMVs) are proteoliposomes shed by Gram-negative bacteria. Their secretion is enhanced by the transition into the intra-host milieu, and OMVs play critical roles during pathogenesis. Enterohemorrhagic Escherichia coli O157 (EHEC) can cause diarrheal disease in humans, and soluble toxins including Shiga-like toxins that contribute to disease severity and clinical complications like hemolytic uremic syndrome have been shown to be OMV associated. In addition to Shiga-like toxins, EHEC produces a type III secretion system (T3SS), and T3SS effectors are associated with colonization and disease severity in vivo. Here, we show that type III secreted substrates including translocators …

Colonization Of Larval Zebrafish (Danio Rerio) With Adherent-Invasive Escherichia Coli Prevents Recovery Of The Intestinal Mucosa From Drug-Induced Enterocolitis, Erika Flores, Soumita Dutta, Rachel Bosserman, Ambro Van Hoof, Anne-Marie Krachler

Faculty, Staff and Student Publications

Although inflammatory bowel diseases are on the rise, what factors influence IBD risk and severity, and the underlying mechanisms remain to be fully understood. Although host genetics, microbiome, and environmental factors have all been shown to correlate with the development of IBD, cause and effect are difficult to disentangle in this context. For example, AIEC is a known pathobiont found in IBD patients, but it remains unclear if gut inflammation during IBD facilitates colonization with AIEC, or if AIEC colonization makes the host more susceptible to pro-inflammatory stimuli. It is critical to understand the mechanisms that contribute to AIEC infections …

Interlaboratory Comparison Of Pseudomonas Aeruginosa Phage Susceptibility Testing, Krupa Parmar, Lauren Komarow, Damon W Ellison, Andrey A Filippov, Mikeljon P Nikolich, Joseph R Fackler, Martin Lee, Anjna Nair, Priyesh Agrawal, Pranita D Tamma, Maria Souli, Scott R Evans, Kerryl E Greenwood-Quaintance, Scott A Cunningham, Robin Patel, Antibacterial Resistance Leadership Group

Faculty, Staff and Student Publications

Standardized approaches to phage susceptibility testing (PST) are essential to inform selection of phages for study in patients with bacterial infections. There is no reference standard for assessing bacterial susceptibility to phage. We compared agreement between PST performed at three centers: two centers using a liquid assay standardized between the sites with the third, a plaque assay. Four Pseudomonas aeruginosa phages: PaWRA01ø11 (EPa11), PaWRA01ø39 (EPa39), PaWRA02ø83 (EPa83), PaWRA02ø87 (EPa87), and a cocktail of all four phages were tested against 145 P. aeruginosa isolates. Comparisons were made within measurements at the two sites performing the liquid assay and between these …

Recombination-Mediated Dissemination Of Methicillin-Resistant S Aureus Clonal Complex 1 In The Egyptian Health Care Settings, Salma W Elsayed, Reem A Elghaish, Eman Badr, Shaimaa F Mouftah, Nehal A Saif, Iman S Naga, Ahmed H Shata, Ben Pascoe, Samuel K Sheppard, Mohamed Elhadidy

Faculty, Staff and Student Publications

Background: Methicillin-resistant Staphylococcus aureus (MRSA) is a rapidly evolving pathogen that is frequently associated with outbreaks and sustained epidemics. This study investigated the population structure, resistome, virulome, and the correlation between antimicrobial resistance determinants with phenotypic resistance profiles of 36 representative hospital-acquired MRSA isolates recovered from hospital settings in Egypt.

Results: The community-acquired MRSA lineage, clonal complex 1 (CC1) was the most frequently detected clone, followed by three other globally disseminated clones, CC121, CC8, and CC22. Most isolates carried SCCmec type V and more than half of isolates demonstrated multi-drug resistant phenotypes. Resistance to linezolid, a last resort antibiotic for …

Development And Validation Of A Multiplex Real-Time Pcr Assay For Detection And Quantification Of Streptococcus Pneumoniae In Pediatric Respiratory Samples, Molly Butler, Garrett Breazeale, Eric Mwangi, Elaine Dowell, Samuel R Dominguez, Linda Lamberth, Kristina G Hultén, Sarah A Jung

Faculty, Staff and Students Publications

Streptococcus pneumoniae (Spn) is a bacterial pathogen that causes a range of disease manifestations in children, from acute otitis media to pneumonia, septicemia, and meningitis. Primary Spn laboratory diagnostic identification methods include culture, antigen testing, single-plex real-time PCR, and syndromic PCR panels. However, each method lacks sensitivity, specificity, and/or cost efficiency. We developed and validated a quantitative, multiplex PCR assay using three Spn genomic targets (lytA, piaB, and SP2020) for improved sensitivity and specificity to detect Spn in pleural fluid (PF), bronchoalveolar lavage (BAL), tracheal aspirate (TA), and upper respiratory (UR, research only) samples. Validation testing …