Microbiology Commons^™

Metabolic Regulator Errγ Governs Gastric Stem Cell Differentiation Into Acid-Secreting Parietal Cells, Mahliyah Adkins-Threats, Sumimasa Arimura, Yang-Zhe Huang, Margarita Divenko, Sarah To, Heather Mao, Yongji Zeng, Jenie Y Hwang, Joseph R Burclaff, Shilpa Jain, Jason C Mills

Faculty, Staff and Students Publications

Parietal cells (PCs) produce gastric acid to kill pathogens and aid digestion. Dysregulated PC census is common in disease, yet how PCs differentiate is unclear. Here, we identify the PC progenitors arising from isthmal stem cells, using mouse models and human gastric cells, and show they preferentially express cell-metabolism regulator and orphan nuclear receptor Estrogen-related receptor gamma (Esrrg, encoding ERRγ). Esrrg expression facilitated the tracking of stepwise molecular, cellular, and ultrastructural stages of PC differentiation. Esrrg^P2ACreERT2 lineage tracing revealed Esrrg expression commits progenitors to differentiate into mature PCs. scRNA-seq indicated the earliest Esrrg+ PC progenitors preferentially …

The Influence Of A Ubiquitous Filter Feeder On Coastal Microbial Communities, Melissa Steinman

Dissertations and Theses

Doliolids are a unique study system for investigating the intricate relationship between pelagic tunicates and the marine microbial community. This study identified the eukaryotic and prokaryotic microbial taxa in wild-caught doliolids in the Northern California Current system. Doliolids were collected during bloom events identified at three different shelf locations with variable upwelling intensity. This study found that doliolids host a microbiome unique from that of the seawater surrounding them and that feeding by doliolids includes a range of prokaryotic microbial functional groups. This is the first study to identify that doliolids are a source of mortality for pelagic archaea, and …

Tetr Family Regulator, Farr, Influences Rot-Mediated Control Of Virulence Factor Expression In Staphylococcus Aureus, Julia C. Schumacher

USF Tampa Graduate Theses and Dissertations

Point-mutation variants of the TetR family regulator, FarR, have emerged across Staphylococcus aureus sequence types as conferring antibiotic and fatty acid resistance, particularly in Hospital-Associated Methicillin Resistant S. aureus (HA-MRSA) strains. FarR also exhibits an additional largely uncharacterized relationship to virulence factor production, seemingly through the global repressor of toxins—Rot, which functions to regulate S. aureus’ ability to colonize and persist in the host via a complex cascade of signaling. While Rot protein is post-transcriptionally regulated by the highly characterized Agr system, there is little known about its transcriptional regulation. Herein, we explored these dynamics by initially characterizing virulence phenotypes …

The Anticancer Activity Of A Novel 8-Hydroxyquinoline Derivatives Against 5-Fluorouracil Resistant Colorectal Cancer Cells, Mazoun Talal Al Azzani

Theses

Cancer is a global health crisis for which 20 million new cases were diagnosed in 2022 alone, with 9.3 million cancer-related deaths. Nearly 900,000 deaths were due to colorectal cancer (CRC), which is the third leading cause of cancer related mortality. In the United Arab Emirates, 550 new cases of CRC were reported in 2022. A major clinical challenge with CRC treatment is the development of resistance to 5-fluorouracil (5FU)-based chemotherapy regimens, which are the standard treatment for CRC. In the present study, the anticancer activity of two novel 8-hydroxyquinoline (8-HQ) derivatives AS45 and AS47 was examined against 5FU-sensitive (HCT116) …

Editorial: The Gut-Skin Axis: Interaction Of Gut Microbiome And Skin Diseases, Jianmin Chai, Feilong Deng, Ying Li, Xiaoyuan Wei, Jiangchao Zhao

Animal Science Faculty Publications and Presentations

Editorial on the Research Topic: The gut-skin axis: interaction of gut microbiome and skin diseases

Hydroponic Nutrient Solution Temperature Impacts Tulane Virus Persistence Over Time, Gayatri R. Dhulappanavar, Kristen E. Gibson

Food Science Faculty Publications and Presentations

Controlled environment agriculture (CEA), or indoor agriculture, encompasses non-traditional farming methods that occur inside climate-controlled structures (e.g., greenhouses, warehouses, high tunnels) allowing for year-round production of fresh produce such as leaf lettuce. However, recent outbreaks and recalls associated with hydroponically grown lettuce contaminated with human pathogens have raised concerns. Few studies exist on the food safety risks during hydroponic cultivation of leaf lettuce; thus, it is important to identify contributing risk factors and potential mitigation strategies to prevent foodborne transmission via hydroponically grown produce. In this study, the concentration of infectious Tulane virus (TV), a human norovirus surrogate, in hydroponic …

Anoctamin 4 Defines Glucose-Inhibited Neurons In The Ventromedial Hypothalamus, Longlong Tu, Yanlin He, Yong Xu

Faculty, Staff and Students Publications

No abstract provided.

Neighborhood-Level Disadvantage And Delayed Adjuvant Therapy In Head And Neck Cancer, Evan M Graboyes, Joshua Lee Cagle, Salma Ramadan, Kavita Prasad, Flora Yan, John Pearce, Angela L Mazul, Jean-Sebastien Anoma, Elizabeth G Hill, Bhisham S Chera, Sidharth V Puram, Ryan Jackson, Vlad C Sandulache, Samantha Tam, Michael C Topf, Russel Kahmke, Nosayaba Osazuwa-Peters, Brian Nussenbaum, Anthony J Alberg, Katherine R Sterba, Chanita Hughes Halbert

Faculty, Staff and Students Publications

Importance: For patients with head and neck squamous cell carcinoma (HNSCC), initiation of postoperative radiation therapy (PORT) within 6 weeks of surgery is recommended by the National Comprehensive Cancer Network Guidelines and the Commission on Cancer. Although individual-level measures of socioeconomic status are associated with receipt of timely, guideline-adherent PORT, the role of neighborhood-level disadvantage has not been examined.

Objective: To characterize the association of neighborhood-level disadvantage with delays in receiving PORT.

Design, setting, and participants: This retrospective cohort study included 681 adult patients with HNSCC undergoing curative-intent surgery and PORT from 2018 to 2020 at 4 US academic medical …

Recombinant Bile Salt Hydrolase Enhances The Inhibition Efficiency Of Taurodeoxycholic Acid Against Clostridium Perfringens Virulence, Tahrir Alenezi, Bilal Alrubaye, Ying Fu, Janashrit Shrestha, Samar Algehani, Hong Wang, Rohana Liyanage, Xiaolun Sun

Chemistry & Biochemistry Faculty Publications and Presentations

Clostridium perfringens is the main pathogen of chicken necrotic enteritis (NE) causing huge economic losses in the poultry industry. Although dietary secondary bile acid deoxycholic acid (DCA) reduced chicken NE, the accumulation of conjugated tauro-DCA (TDCA) raised concerns regarding DCA efficacy. In this study, we aimed to deconjugate TDCA by bile salt hydrolase (BSH) to increase DCA efficacy against the NE pathogen C. perfringens. Assays were conducted to evaluate the inhibition of C. perfringens growth, hydrogen sulfide (H₂S) production, and virulence gene expression by TDCA and DCA. BSH activity and sequence alignment were conducted to select the …

Dietary Probiotic Supplement Attenuates Methamphetamine-Induced Conditioned Place Preference In Female Sprague-Dawley Rats, Kristen Powell

Masters Theses

Substance use disorders (SUD) represent a global public health crisis with limited effective treatment options. Recent findings implicate the gut microbiome and gut/brain axis in the pathophysiology of SUDs. Several preclinical studies have established that psychostimulants alter gut microbiome composition, but no published studies have assessed behavioral effects of dietary probiotic supplements on drug-induced behavioral changes. This study utilized rodent conditioned place preference (CPP) as a behavioral index of conditioned drug reward to determine if a dietary probiotic supplement alters the behavioral effects of (+)-methamphetamine (METH). Fifty-four adult female Sprague-Dawley rats were randomly assigned to receive either a standard rodent …

Serum Extracellular Vesicle Protein Profiling For Prediction Of Corneal Transplant Rejection, Hyun Ju Lee, Eun-Hye Bae, Jong Min Choi, Hyemee Kim, Hyeon Ji Kim, Heather Barreda, Sung Yun Jung, Joo Youn Oh, Ryang Hwa Lee

Faculty, Staff and Students Publications

Background: Corneal transplantation is the most common transplant procedure worldwide. Despite immune and angiogenic privilege of the cornea, 50% to 70% of corneal transplants fail in high-risk recipients, primarily because of immune rejection. Therefore, it is crucial to identify predictive biomarkers of rejection to improve transplant survival.

Methods: In search for predictive biomarkers, we performed proteomics analysis of serum extracellular vesicles (EVs) in a fully major histocompatibility complex-mismatched (C57BL/6-to-BALB/c) murine corneal transplantation model, wherein 50% of transplants undergo rejection by day 28 following transplantation.

Results: Our time course study revealed a decrease in the number of serum EVs on day …

Multifactoral Immune Modulation Potentiates Durable Remission In Multiple Models Of Aggressive Malignancy, Matthew M Halpert, Briana A Burns, Spencer R Rosario, Henry G Withers, Akshar J Trivedi, Colby J Hofferek, Benjamin D Gephart, Haotong Wang, Jonathan Vazquez-Perez, Sharon B Amanya, Sean T Hyslop, Jianhua Yang, Jan O Kemnade, Vlad C Sandulache, Vanaja Konduri, William K Decker

Faculty, Staff and Students Publications

Tumors typically lack canonical danger signals required to activate adaptive immunity and also frequently employ substantial immunomodulatory mechanisms that downregulate adaptive responses and contribute to escape from immune surveillance. Given the variety of mechanisms involved in shielding tumors from immune recognition, it is not surprising that single-agent immunomodulatory approaches have been largely unsuccessful in generating durable antitumor responses. Here we report a unique combination of immunomodulatory and cytostatic agents that recondition the tumor microenvironment and eliminate complex and/or poor-prognosis tumor types including the non-immunogenic 4T-1 model of TNBC, the aggressive MOC-2 model of HNSCC, and the high-risk MYCN-amplified model of …

Generation Of Oviductal Glycoprotein 1 Cre Mouse Model For The Study Of Secretory Epithelial Cells Of The Oviduct, Emily A Mcglade, Jiude Mao, Kalli K Stephens, Andrew M Kelleher, Lisette A Maddison, Miranda L Bernhardt, Francesco J Demayo, John P Lydon, Wipawee Winuthayanon

Faculty, Staff and Students Publications

The epithelial cell lining of the oviduct plays an important role in oocyte pickup, sperm migration, preimplantation embryo development, and embryo transport. The oviduct epithelial cell layer comprises ciliated and nonciliated secretory cells. The ciliary function has been shown to support gamete and embryo movement in the oviduct, yet secretory cell function has not been well characterized. Therefore, our goal was to generate a secretory cell-specific Cre recombinase mouse model to study the role of the oviductal secretory cells. A knock-in mouse model, Ovgp1Cre:eGFP, was created by expressing Cre from the endogenous Ovgp1 (oviductal glycoprotein 1) locus, with enhanced green …

The Interplay Of Gut Microbiota And Their Metabolites As Potential Regulators Of Resilience Or Susceptibility To Traumatic Stress In Male And Female Rats, Arax Tanelian

NYMC Student Theses and Dissertations

Exposure to traumatic stress is a major risk factor for the development of mood disorders in a subpopulation of individuals, while others remain resilient. Notably, women are twice as likely as men to develop affective disorders in the aftermath of trauma. The mechanisms and contributing factors that influence sex-related disparities in mood disorders and variations in resilience remain unclear. We hypothesized that sex-specific inter-individual differences in microbial composition, functionality, and metabolites would contribute to host resilience or susceptibility to stress-induced psychopathologies. In this study, we used single prolonged stress (SPS), an animal model of Post- Traumatic Stress Disorder (PTSD), to …

A Potential Of Watercress Nasturtium Officinale Bioactive Compounds In Inhibiting Infectious Myonecrosis Virus (Imnv) By Targeting Rna-Dependent Rna Polymerase (Rdrp) Virus From Several Countries: In Silico Approach, Qurrota A’Yunin, Fatchiyah Fatchiyah, Maftuch Maftuch, Feri Eko Hermanto, Muhammad Hermawan Widyananda, Narendra Santika Hartana, Muhaimin Rifa’I, Yoga Dwi Jatmiko

Karbala International Journal of Modern Science

Infectious myonecrosis virus (IMNV) disease causes mass mortality and decreased shrimp production. The RdRp region projects to the interior, where it may function in transcription. The focus of this study was to determine the effect of amino acid polymorphisms from several countries on the structure of RdRp and identify the potential of watercress in inhibiting IMNV by targeting the RdRp protein of IMNV through an in silico approach. The results showed that the structure of the IMNV RdRp protein from Indonesia was similar to Mexico, and the protein structure from India_QDN was identical to India_QIL. Ligand binding affinity values showed …

Impact Of Toll-Like Receptor 10 Mutations On Tuberculosis Infections, Adriana Nicole Rafael, Sangman Kim

Master's Theses

Tuberculosis (TB), caused by the intracellular pathogen Mycobacterium tuberculosis (M. tb), is a leading global health crisis causing millions of cases and deaths each year. Though it affects individuals of any race, ethnicity, or cultural group, research shows the disease disproportionately affects individuals with Asian ancestry. Immunity to M. tb starts with its recognition by pattern recognition receptors such as Toll-like receptors (TLRs), which are key players in immune responses. TLR-10, an understudied toll-like receptor due to its inability to be studied through mouse models, is thought to play a key role in the clearance of inflammatory diseases. SNP I775V, …

Antibiotic-Induced Changes In Efflux Transporter Expression: A Key Factor In Pseudomonas Aeruginosa Biofilm Resistance, Zara Imtiaz, Avinash Chatoo, Will Wang, Weiqi Li, Paramita Basu

Touro College of Pharmacy (New York) Publications and Research

Listed by WHO as an antibiotic-resistant priority pathogen, Pseudomonas aeruginosa(P.A.) is a serious threat in nosocomial infections. Its high antibiotic resistance is attributed to major mechanisms that can be categorized into intrinsic, acquired, and adaptive resistance. This study tests the ability of three commonly used antibiotics to inhibit new biofilm formation and eradicate mature biofilm growth, as well as investigate changes in the expression levels of selected genes coding for multidrug efflux pumps in P.A. planktonic cells and biofilms before and after treatment with antibiotics to provide a conceptual estimate of the activity of the efflux transporters that work to …

Delivering Crispr To The Hiv-1 Reservoirs, Theodore Gurrola, Samuel Effah, Ilker Sariyer, Will Dampier, Michael Nonnemacher, Brian Wigdahl

Kimmel Cancer Center Faculty Papers

Human immunodeficiency virus type 1 (HIV-1) infection is well known as one of the most complex and difficult viral infections to cure. The difficulty in developing curative strategies arises in large part from the development of latent viral reservoirs (LVRs) within anatomical and cellular compartments of a host. The clustered regularly interspaced short palindromic repeats/ CRISPR-associated protein 9 (CRISPR/Cas9) system shows remarkable potential for the inactivation and/or elimination of integrated proviral DNA within host cells, however, delivery of the CRISPR/Cas9 system to infected cells is still a challenge. In this review, the main factors impacting delivery, the challenges for delivery …

Optical Coherence Tomography-Guided Brillouin Microscopy Highlights Regional Tissue Stiffness Differences During Anterior Neural Tube Closure In The Mthfd1l Murine Mutant, Yogeshwari S Ambekar, Carlo Donato Caiaffa, Bogdan J Wlodarczyk, Manmohan Singh, Alexander W Schill, John W Steele, Jitao Zhang, Salavat R Aglyamov, Giuliano Scarcelli, Richard H Finnell, Kirill V Larin

Faculty, Staff and Students Publications

Neurulation is a highly synchronized biomechanical process leading to the formation of the brain and spinal cord, and its failure leads to neural tube defects (NTDs). Although we are rapidly learning the genetic mechanisms underlying NTDs, the biomechanical aspects are largely unknown. To understand the correlation between NTDs and tissue stiffness during neural tube closure (NTC), we imaged an NTD murine model using optical coherence tomography (OCT), Brillouin microscopy and confocal fluorescence microscopy. Here, we associate structural information from OCT with local stiffness from the Brillouin signal of embryos undergoing neurulation. The stiffness of neuroepithelial tissues in Mthfd1l null embryos …

Seasonality, Clinical Characteristics, And Outcomes Of Respiratory Syncytial Virus Disease By Subtype Among Children Aged <5 Years: New Vaccine Surveillance Network, United States, 2016-2020, Ariana P Toepfer, Justin Z Amarin, Andrew J Spieker, Laura S Stewart, Mary Allen Staat, Elizabeth P Schlaudecker, Geoffrey A Weinberg, Peter G Szilagyi, Janet A Englund, Eileen J Klein, Marian G Michaels, John V Williams, Rangaraj Selvarangan, Christopher J Harrison, Joana Y Lively, Pedro A Piedra, Vasanthi Avadhanula, Brian Rha, James Chappell, Meredith Mcmorrow, Heidi Moline, Natasha B Halasa

Faculty, Staff and Students Publications

BACKGROUND: Respiratory syncytial virus (RSV) is a leading cause of acute respiratory illnesses in children. RSV can be broadly categorized into 2 major subtypes: A and B. RSV subtypes have been known to cocirculate with variability in different regions of the world. Clinical associations with viral subtype have been studied among children with conflicting findings such that no conclusive relationships between RSV subtype and severity have been established.

METHODS: During 2016-2020, children aged/guardian interviews, chart reviews, and collection of midturbinate nasal plus/minus throat swabs for RSV (RSV-A, RSV-B, and untyped) using reverse transcription polymerase chain reaction.

RESULTS: Among 6398 RSV-positive …

Biogeographic Patterns In Phyllosphere Bacterial Communities On Southern Magnolia Trees In A Small Town, Elizabeth M. Eckard, Venkat K. Kota, Kurre T. Luber

Honors Theses

The phyllosphere, consisting of aerial plant surfaces colonized by microorganisms, remains a relatively understudied ecosystem in terms of bacterial biogeography, particularly at intermediate spatial scales. This study characterized the bacterial community on the leaves of 89 Magnolia grandiflora trees throughout a small town, encompassing an area of approximately 60 km². Sequencing of the 16S ribosomal RNA gene revealed the dominant bacterial phyla to be Alphaproteobacteria, Bacteroidetes, and Acidobacteria, consistent with other studies of the phyllosphere. Unlike other studies over smaller spatial scales, there was no significant relationship between phyllosphere community similarity and distance between trees (i.e., trees further …

Characterization Of A Novel Metalloid Reductase Outer Membrane Porin Rara From Sulfurospirillum Barnesii Ses-3, Narthana Jeganathar Kanmanii

Electronic Theses and Dissertations

Sulfurospirillum barnesii SES-3 is a gram-negative epsilon proteobacterium that grows anaerobically by coupling the oxidation of lactate to the reduction of arsenate. Previous work on metal and metalloid metabolism in S. barnesii had identified a redox active protein, designated RarA that when provided an artificial electron donor (i.e., reduced methyl viologen, FMN, or NADH), could reduce a variety of substrates, including arsenate, selenate, selenite, nitrite, and even phosphate. The enzyme’s inferred amino acid sequence showed weak similarity (30%) to outer membrane porins with homologs found in only certain species of Sulfurospirillum. Further, the enzyme did not contain cysteine residues …

Greening The Edge: Investigating Riparian Buffer Restorations In A Pastoral Setting And Their Effects On Soil Carbon And Microbial Community Composition., Seth Mccullough

Masters Theses, 2020-current

Riparian buffer restoration represents a critical strategy for enhancing ecosystem health and resilience in agricultural landscapes. This study investigates the effects of riparian buffer restoration on soil properties, microbial communities, and carbon dynamics in Rockingham County, VA. Through a comprehensive field study, we assessed the physicochemical properties of soil, microbial biomass, community composition, and soil carbon storage in restored and unrestored riparian buffers. Our findings reveal significant improvements in soil physical properties in restored buffers, including increased soil moisture (p < 0.05) and decreased bulk density (p < 0.01), indicating enhanced soil structure and water retention capacity. While no significant differences were detected in soil pH or cation exchange capacity, restored buffers exhibited higher soil carbon stocks (p < 0.05) and carbon-to-nitrogen ratios, suggesting potential differences in nutrient cycling processes and organic matter decomposition rates. Moreover, restored buffers showed increased microbial biomass (p < 0.01), potentially driven by improved habitat conditions and shifts towards a fungal-dominated microbial community.

Although no significant differences were found in overall microbial community composition between restored and unrestored sites, specific shifts in bacterial …

The Influence Of A Ubiquitous Filter Feeder On Coastal Microbial Communities., Melissa Steinman, Moritz S. Schmid, Robert K. Cowen, Su Sponaugle, Kelly R. Sutherland, Anne W. Thompson

Student Research Symposium

Doliolids have a unique ability to impact the marine microbial community through bloom events and high filtration rates. Their predation on large eukaryotic microorganisms is established and evidence of predation on smaller prokaryotic microorganisms is beginning to emerge. We studied the retention of both eukaryotic and prokaryotic microbial taxa by wild-caught doliolids in the northern California Current system. We use qPCR to quantify the impact of doliolids on three important and globally abundant taxa: Synechococcus, SAR11 and diatoms. Doliolids were collected during bloom events identified at three different shelf locations with variable upwelling intensities. We discovered that in addition …

Role Of Integrase-Pp2a Interaction In Human T-Cell Leukemia Virus Type-1 Replication And Pathogenesis, Shayna Turbin

Senior Honors Papers / Undergraduate Theses

Human T-cell leukemia virus type-1 (HTLV-1) is an oncogenic retrovirus that causes multiple disorders, including adult T-cell leukemia and HTLV-1-associated myelopathy/tropical spastic paraparesis. HTLV-1 retroviral integrase binds to the regulatory B’56γ subunit of the host cell Protein Phosphatase 2A (PP2A). Integrase contains a highly conserved LxxIxE motif that is essential for binding, which increases integration efficiency and facilitates HTLV-1 hijack of host cell machinery. We aim to understand how mutations introduced in the highly conserved binding site can affect viral particle production and infectivity. We transfected 729B human lymphoblastoid cells and 293T cells with mutant and wildtype virus. Mutations L213A, …

Progress Toward A Vaccine For Extraintestinal Pathogenic Coli (Expec) Ii: Efficacy Of A Toxin-Autotransporter Dual Antigen Approach, Yikun Xing, Justin R Clark, James D Chang, Jacob J Zulk, Dylan M Chirman, Felipe-Andres Piedra, Ellen E Vaughan, Haroldo J Hernandez Santos, Kathryn A Patras, Anthony W Maresso

Faculty, Staff and Students Publications

Extraintestinal pathogenic Escherichia coli (ExPEC) is a leading cause of worldwide morbidity and mortality, the top cause of antimicrobial-resistant (AMR) infections, and the most frequent cause of life-threatening sepsis and urinary tract infections (UTI) in adults. The development of an effective and universal vaccine is complicated by this pathogen’s pan-genome, its ability to mix and match virulence factors and AMR genes via horizontal gene transfer, an inability to decipher commensal from pathogens, and its intimate association and co-evolution with mammals. Using a pan virulome analysis of >20,000 sequenced E. coli strains, we identified the secreted cytolysin α-hemolysin (HlyA) as a …

Lmpact Of Salmonella Enterica Effector Proteins On Plant Physiology And Immunity, Sara Qader

Honors Theses

Salmonella enterica serovar Typhimurium are primarily recognized as pathogens associated with foodborne illnesses in humans. Salmonella also can colonize plant tissue effectively. The pathogen relies on type III secretion systems (T3SS) to infect mammals and plants successfully and counteract the immune response. Understanding the molecular mechanisms underlying Salmonella’s interactions with plants is essential for developing effective strategies to reduce its impact on human health and agriculture. Effector proteins, known for their role in modulating host-pathogen interactions, have been implicated in the virulence and pathogenicity of Salmonella. However, their specific functions and contributions to Salmonella’s interactions with plants remain largely unknown. …

Metaplastic Regeneration In The Mouse Stomach Requires A Reactive Oxygen Species Pathway, Zhi-Feng Miao, Jing-Xu Sun, Xuan-Zhang Huang, Shi Bai, Min-Jiao Pang, Jia-Yi Li, Han-Yu Chen, Qi-Yue Tong, Shi-Yu Ye, Xin-Yu Wang, Xiao-Hai Hu, Jing-Ying Li, Jin-Wei Zou, Wen Xu, Jun-Hao Yang, Xi Lu, Jason C Mills, Zhen-Ning Wang

Faculty, Staff and Students Publications

In pyloric metaplasia, mature gastric chief cells reprogram via an evolutionarily conserved process termed paligenosis to re-enter the cell cycle and become spasmolytic polypeptide-expressing metaplasia (SPEM) cells. Here, we use single-cell RNA sequencing (scRNA-seq) following injury to the murine stomach to analyze mechanisms governing paligenosis at high resolution. Injury causes induced reactive oxygen species (ROS) with coordinated changes in mitochondrial activity and cellular metabolism, requiring the transcriptional mitochondrial regulator Ppargc1a (Pgc1α) and ROS regulator Nf2el2 (Nrf2). Loss of the ROS and mitochondrial control in Ppargc1a-/- mice causes the death of paligenotic cells through ferroptosis. Blocking the cystine transporter SLC7A11(xCT), which …

Impact Of Salmonella Enterica On Plant Physiology And Immunity, Sara Qader

Poster Presentations

Salmonella can colonize plant tissue effectively. Understanding the molecular mechanisms underlying Salmonella’s interactions with plants is essential for developing effective strategies to reduce its impact on human health and agriculture. Effector proteins, known for their role in modulating host-pathogen interactions, have been implicated in the virulence and pathogenicity of Salmonella. However, their specific functions and contributions to Salmonella’s interactions with plants remain largely unknown. Here, we aim to investigate the functions of Salmonella effector proteins during the colonization of plants.

The Physiological Significance Of Nitric Oxide Synthase In Staphylococci, Ryan M. Singh

Theses & Dissertations

Staphylococci, particularly Staphylococcus epidermidis, are common causes of implant-associated infections that may result in notable morbidity and mortality. One of the ways the innate immune system attempts to combat these invading pathogens is via the respiratory burst, in which free radical species such as nitric oxide (NO^•), toxic to bacterial respiration, are released in large quantities. Despite the toxicity of NO^•, some bacteria, including staphylococci, encode an endogenous bacterial nitric oxide synthase (bNOS), whose physiological role has been unclear until now. In this dissertation, we demonstrate that S. epidermidis is able to overcome the toxicity …