Microbiology Commons^™

In Silico Prediction Of Cytotoxic T-Cell Epitopes From Helicobacter Pylori Virulence Factors Using An Immunoinformatics Approach, Demy Valerie Chacon, Kiana Alika Co, Daphne Noreen Enriquez, Aubrey Love Labarda, Reanne Eden Manongsong, Edward Kevin B. Bragais

Biology Faculty Publications

Background: Helicobacter pylori infects approximately half of the global population, leading to gastric and duodenal ulcers. Despite the availability of antibiotics, challenges such as patient reluctance, high treatment costs, and antibiotic resistance limit their effectiveness, making vaccination a promising alternative. This study used immunoinformatics to identify candidate epitopes for a multiepitope vaccine construct against H. pylori.

Material and methods: The protein variability server was utilized for conservation analysis. The epitopes were screened for antigenicity, allergenicity, toxicity, cross-reactivity, and population coverage. Selected epitopes were docked with their corresponding human leukocyte antigen (HLA) alleles, and thermodynamic quantities were determined. Five virulence …

Phosphoglycerate Mutase Regulates Treg Differentiation Through Control Of Serine Synthesis And One-Carbon Metabolism, Wesley H Godfrey, Judy J Lee, Shruthi Shanmukha, Kaho Cho, Xiaojing Deng, Chandra Shekar R Ambati, Vasanta Putluri, Abu Hena Mostafa Kamal, Paul M Kim, Nagireddy Putluri, Michael D Kornberg

Faculty, Staff and Students Publications

The differentiation and suppressive functions of regulatory CD4 T cells (Tregs) are supported by a broad array of metabolic changes, providing potential therapeutic targets for immune modulation. In this study, we focused on the regulatory role of glycolytic enzymes in Tregs and identified phosphoglycerate mutase (PGAM) as being differentially overexpressed in Tregs and associated with a highly suppressive phenotype. Pharmacologic or genetic inhibition of PGAM reduced Treg differentiation and suppressive function while reciprocally inducing markers of a pro-inflammatory, T helper 17 (Th17)-like state. The regulatory role of PGAM was dependent on the contribution of 3-phosphoglycerate (3 PG), the PGAM substrate, …

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

Faculty, Staff and Students Publications

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

Mouse Metastable Epialleles Are Extremely Rare, Chathura J Gunasekara, Uditha Maduranga, Taylor Zhang, Jonathan N Wells, Maria S Baker, Eleonora Laritsky, Yumei Li, Cristian Coarfa, Yi Zhu, Robert A Waterland

Faculty, Staff and Students Publications

Metastable epialleles (MEs) are genomic loci at which epigenetic marks are established stochastically during early embryonic development and maintained during subsequent differentiation and throughout life, leading to stable epigenetic and phenotypic variation among genetically identical individuals. Although MEs were first described in mice over 20 years ago, the extent of epigenetic metastability in the mouse genome remains unknown. We present the first unbiased genome-wide screen for MEs in mice. Using deep whole-genome bisulfite sequencing across tissues derived from the three embryonic germ layers in isogenic C57BL/6J mice, we identified only 29 MEs, precisely localizing them and documenting their rarity. Consistent …

Altered Patterning Of Neural Activity In A Neuropathology, Clarissa Hoffman, Jingheng Cheng, Rodrigo Morales, Daoyun Ji, Yuri Dabaghian

Faculty, Staff and Students Publications

The dynamics of neural circuits and their role in mediating cellular and organismal phenomena remain poorly understood, despite numerous efforts to dissect these processes through precise instantaneous measurements or longer-time averages and approximations. We use an alternative approach: we investigate these dynamics at the system's mesoscale by analyzing spike trains and waveforms. These extended activity patterns carry robust, tractable information, are highly responsive to physiological specifics, and enable detailed tracking of circuit behavior. In particular, this methodology allows for characterizing the functionality of tau-pathology-afflicted hippocampal circuits and identifying circuit-level abnormalities that are missed by through traditional analyses. In healthy mice, …

Exogenous Arginine Differentially Regulates Inflammatory Cytokine And Inducible Nitric Oxide Synthase Expression In Macrophages, Kelsey Stayer, Saliha Pathan, Aalekhya Biswas, Huiqiao Li, Yi Zhu, Fong Wilson Lam, Juan Marini, Sundararajah Thevananther

Faculty, Staff and Students Publications

Immune dysfunction and late mortality from multiorgan failure are hallmarks of severe sepsis. Arginine, a semi-essential amino acid important for protein synthesis, immune response, and circulatory regulation, is deficient in sepsis. However, arginine supplementation in sepsis remains controversial due to the potential to upregulate inducible nitric oxide synthase (iNOS)-mediated excessive nitric oxide (NO) generation in macrophages, leading to vasodilation and hemodynamic catastrophe. Citrulline supplementation has been considered an alternative to replenishing arginine via de novo synthesis, orchestrated by argininosuccinate synthase 1 (ASS1) and argininosuccinate lyase (ASL). However, the functional relevance of the ASS1-ASL pathway in macrophages after endotoxin stimulation is …

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

Faculty, Staff and Students Publications

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

Single-Cell Profiling Of Bone Metastasis Ecosystems From Multiple Cancer Types Reveals Convergent And Divergent Mechanisms Of Bone Colonization, Fengshuo Liu, Yunfeng Ding, Zhan Xu, Xiaoxin Hao, Tianhong Pan, George Miles, Siyue Wang, Yi-Hsuan Wu, Jun Liu, Igor L Bado, Weijie Zhang, Ling Wu, Yang Gao, Liqun Yu, David G Edwards, Hilda L Chan, Sergio Aguirre, Michael Warren Dieffenbach, Elina Chen, Yichao Shen, Dane Hoffman, Luis Becerra Dominguez, Charlotte Helena Rivas, Xiang Chen, Hai Wang, Zbigniew Gugala, Robert L Satcher, Xiang H-F Zhang

Faculty, Staff and Students Publications

Bone is a common site for metastasis of solid cancers. The diversity of histological and molecular characteristics of bone metastases (BMs) remains poorly studied. Here, we performed single-cell RNA sequencing on 42 BMs from eight cancer types, identifying three distinct ecosystem archetypes, each characterized by an enrichment of specific immune cells: macrophages/osteoclasts, regulatory/exhausted T cells, or monocytes. We validated these archetypes by immunostaining on tissue sections and bioinformatic analysis of bulk RNA sequencing/microarray data from 158 BMs across more than 10 cancer types. Interestingly, we found only a modest correlation between the BM archetypes and the tissues of origin; BMs …

Commentary On Blaser's "Antibiotic Use And Its Consequences For The Normal Microbiome", Fred C. Tenover

AMR Commentary

If you have not read this eye-opening commentary by Dr. Martin Blaser about the negative impact of the widespread use of antibiotics in children, you should. The goal of giving antibiotics to children usually is to treat an infection — an earache, a respiratory tract infection, or perhaps a potentially deadly bloodstream infection. Those antibiotics, however, will often kill more than just the bacteria that are causing the infection. Humans have large quantities of “good bacteria” in our intestinal tracts, on our skin, and elsewhere on our body that play an important role in keeping us healthy.

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

Faculty, Staff and Students Publications

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

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

Faculty, Staff and Students Publications

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

Inhibition Of The Gsk3Β/Nav16 Complex Suppresses Early-Stage Alzheimer’S Hyperexcitability, Timothy John Baumgartner, Manuel Silva-Pérez, Zahra Haghighijoo, Nolan Michael Dvorak, Aditya Kumar Singh, Nana Aboadwe Goode, Jully Singh, Berenice Gutierrez Grebenkova, Mate Marosi, Jessica Di Re, Leandra Koff, Wissarut Wijitrmektong, Manu Bala, Hanyue Liao, Marijn Lijffijt, Adam Thomas Szafran, Michael James Bolt, Michael A Mancini, Gregory D Cuny, Diana Shu-Lian Chow, Agenor Limon, Jeannie Chin, Fernanda Laezza

Faculty, Staff and Students Publications

Introduction: Network hyperexcitability (NH) is observed in patients with early-stage Alzheimer's disease (AD), emerging decades before cognitive decline. A key molecular determinant of NH is voltage-gated Na+ channel 1.6 (Nav1.6), which mediates action potential firing in CA1 hippocampal neurons. Ameliorating NH through inhibition of the glycogen-synthase kinase 3β (GSK3β/Nav1.6 complex may provide immediate benefits to cognition and memory and slow AD progression.

Methods: Hight-throughput virtual screening and multiple in vitro biological assays were utilized to identify compound 1063. Patch-clamp electrophysiology and electroencephalogram recordings were utilized to functionally assess 1063 in models of AD neuropathology.

Results: Building on previous studies identifying …

Decoding Metastatic Microenvironments Through Single-Cell Omics Reveals New Insights Into Niche Dynamics And Tumor Evolution, Fengshuo Liu, Xiang H-F Zhang

Faculty, Staff and Students Publications

Metastasis is the predominant cause of cancer mortality, primarily driven by complex tumor-host interactions within specialized metastatic niches. Recent advances in single-cell technologies have provided unprecedented insights into metastatic niche formation, evolution and function, including how primary tumors precondition distant organs for metastases and how disseminated tumor cells dynamically interact with host cells to modulate their environments. Integrated single-cell studies across multiple cancer types have also revealed divergent and convergent metastatic adaptation strategies. These findings collectively highlight metastasis as a dynamic, cooperative process shaped by intricate tumor-host interactions, and provide a foundation for novel therapeutic strategies targeting components of the …

Association Of Statin Use On Survival Outcomes Of Patients With Early-Stage Her2-Positive Breast Cancer In The Aphinity Trial, Christian Maurer, Elisa Agostinetto, Lieveke Ameye, Matteo Lambertini, Samuel Martel, Noam Ponde, Mariana Brandão, Francesca Poggio, Arlindo Ferreira, Rachel Schiff, Carmine De Angelis, Richard D Gelber, Susan Dent, Christoph Thomssen, Martine Piccart, Evandro De Azambuja

Faculty, Staff and Students Publications

Purpose: There is evidence that statins might improve the outcome of patients with breast cancer. The role of statins in patients with early HER2-positive breast cancer is unknown. Therefore, we explored the association between statin use and survival outcomes in early HER2-positive breast cancer patients in the phase III APHINITY trial (adjuvant pertuzumab/trastuzumab).

Methods: All patients (intent-to-treat population, n = 4804) were included (6.2 years median follow-up database). The primary objective was to investigate the association of statin use on invasive disease-free survival (IDFS), distant relapse-free interval (DRFI), and overall survival (OS). Patients who received statins at baseline, or started …

Reaction Control Mechanism In Deoxyuridine 5'-Triphosphate Nucleotidohydrolase, Aaron Delay

School of Biological Sciences: Dissertations, Theses, and Student Research

Deoxyuridine 5'-triphosphate nucleotidohydrolase (dUTPase) is an enzyme involved in the pyrimidine biosynthesis pathway, a key component of cellular DNA metabolism. It regulates intracellular uracil carrying triphosphate levels by hydrolyzing dUTP, thereby providing a substrate for thymidylate synthase (TS). The effective inhibition of dUTPase is expected to enhance TS-targeted chemotherapy by promoting thymine-less apoptosis.

Although the reaction mechanism of dUTPase has been studied, the human nuclear homotrimeric form remains complex, as all three subunits cooperatively form a single active site. As a result, the detailed molecular dynamics of its catalysis are still not fully understood. In this study, I investigated the …

Phytochemical Analysis And Antimicrobial Activity Of Micromeria Barbata Leaf And Stem Extracts Against Pseudomonas Aeruginosa: Insights From Molecular Docking And In Vitro Assays, Shiraz Rawas, Dalia El-Badan, Nawal Al Hakawati

BAU Journal - Science and Technology

The present study provides the characterization of the phytochemical content and the antibacterial activity of ethanolic extracts from the leaves (LM) and stems (SM) of Micromeria barbata (M.barbata) against Pseudomonas aeruginosa . Important functional groups were determined by analyzing the FTIR spectra of LM and SM. The phytochemical profiles were analyzed by GC-MS, and these characterized the chemicals according to retention periods and peak regions. The binding affinities of discovered compounds with the P. aeruginosa LasR and PqsD proteins were evaluated using molecular docking approach. Assays for biofilm formation, MIC, MBC, and agar well diffusion were used to assess the …

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

Journal of Bioresource Management

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

Abstract 2587 Recombinant Expression And Purification Of A. Vinelandii Cown In E. Coli, Julie Takei, Cedric P. Owens, Katie Sanders, Neeraja Gajendran

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The goal of this project is to study the protein CowN in the diazotroph Azotobacter vinelandii (Av) in comparison to CowN in Gluconacetobacter diazotrophicus (Gd). Nitrogenase is an enzyme that catalyzes the reduction of nitrogen gas into ammonia in diazotrophic bacteria. In many diazotrophs, the protein CowN prevents nitrogenase inhibition from the environmental gas carbon monoxide (CO). Previous work studied CowN in the diazotroph G. diazotrophicus. In G. diazotrophicus, CowN binds to nitrogenase and weakens CO binding to its active site. The mechanism of CowN has only been investigated in G. diazotrophicus. Thus, we are interested in determining if CowN's …

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

Faculty, Staff and Students Publications

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

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

Faculty, Staff and Students Publications

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

Parp Inhibitor Response Is Enhanced In Prostate Cancer When Xrcc1 Expression Is Reduced, Kaveri Goel, Vani Venkatappa, Kimiko L Krieger, Dongquan Chen, Arun Sreekumar, Natalie R Gassman

Faculty, Staff and Students Publications

Prostate cancer (PCa) is the second most common cancer worldwide and the fifth leading cause of cancer-related deaths among men. The emergence of metastatic castration-resistant prostate cancer (mCRPC) after androgen deprivation therapy (ADT) exemplifies the complex disease management for PCa. PARP inhibitors (PARPis) are being tested to treat mCRPC in tumors with defective homologous recombination repair (HRR) to address this complexity. However, increasing resistance towards PARPi in HRR-deficient patients and the low percentage of HRR-defective mCRPC patients requires the identification of new genes whose deficiency can be exploited for PARPi treatment. XRCC1 is a DNA repair protein critical in the …

Stress, Employment Changes, And Psychological Distress Among Caregivers Of Patients With Head And Neck Cancer, Lama Abdurrahman, Vlad C Sandulache, Cielito Reyes-Gibby, Erich M Sturgis, Pavan Jhaveri, Hoda Badr

Faculty, Staff and Students Publications

Importance: Patients undergoing external beam radiation therapy (EBRT) for head and neck cancer (HNC) often experience adverse effects that require substantial caregiving. The burdens of caregiving can impact caregiver employment and mental health over time, yet this topic remains underexplored.

Objective: To examine the associations between caregiving for patients with HNC who undergo EBRT and caregiver stress, employment status, and psychological distress.

Design, setting, and participants: This was a secondary analysis of data from a longitudinal survey study that surveyed caregivers at baseline (ie, at initiation of EBRT) and at 4-month and 12-month follow-ups. The study was conducted at 2 …

The Aging Ovary Stands On The Shoulders Of Giant Multinucleated Cells, Avery A Ahmed, Stephanie A Pangas

Faculty, Staff and Students Publications

Reproductive aging is associated with declining fertility and increasing inflammation, though these events are not well understood. An exciting new study in PLOS Biology utilizes cutting-edge technologies to characterize the role of multinucleated giant cells in ovarian aging.

Digesting The Details: How Cooking Shapes The Microbiome And Influences Obesity, Tracy Lieu

University Honors Theses

Obesity is a growing global health concern linked to chronic diseases and changes in the gut microbiome. While diet is known to affect gut microbes, less attention has been given to how food processing methods, such as heating, fermentation, and cold processing, change food in ways that influence the gut microbiome and health. This thesis reviews research on how different cooking and preparation techniques affect the availability of nutrients for microbial fermentation and the resulting effects on microbial diversity and metabolism. The findings show that fermentation and cold processing are the most supportive of gut health. These methods help preserve …

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

Research Days

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

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

Oral Prevalence Of Selenomonas Noxia Differs Among Orthodontic Patients Compared To Non-Orthodontic Controls: A Retrospective Biorepository Analysis, Kyle Hodges

UNLV Theses, Dissertations, Professional Papers, and Capstones

Introduction: The introduction of fixed orthodontic brackets in orthodontic therapy has the potential to significantly alter the oral microbial flora. Most orthodontic research has focused on cariogenic pathogens, while some evidence has demonstrated an increase in many known periodontal pathogens. However, little is known about the prevalence of the gram-negative periodontal pathogen, Selenomonas noxia (SN) among these patients.Methods: Using an existing saliva biorepository, n=208 samples from adult and pediatric orthodontic and non-orthodontic patients were identified and screened for the presence of SN using qPCR and validated primers. Results: In the pediatric study sample (n=89) 36% tested positive for the presence …

Investigating The Influence Of Environmental Stressors To Exopolysaccharide Production In Soil Cyanobacteria: Genomic And Physiological Perspectives, Benjy Sedano-Herrera

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cyanobacteria are photosynthetic microbes with essential roles in Earth’s ecosystems. The secretion of long–chain polysaccharides, known as exopolysaccharides (EPS), is a key trait facilitating cyanobacterial adaptation to diverse ecosystems. Genomics studies have shown that aquatic cyanobacteria harbor multiple gene copies encoding EPS export proteins, likely conferring a selective advantage in lakes or oceans. In addition, physiological experiments showed that nutrient limitation in aquatic habitats influences EPS production, affecting cyanobacterial fitness. However, whether terrestrial cyanobacteria also harbor multiple EPS-related genes and how nutrient limitation impacts their EPS production is not well understood.In the first chapter of my thesis, we investigated the …

Theta Oscillons In Behaving Rats, M S Zobaer, Nastaran Lotfi, Carli M Domenico, Clarissa Hoffman, Luca Perotti, Daoyun Ji, Yuri Dabaghian

Faculty, Staff and Students Publications

Recently discovered constituents of the brain waves—the oscillons—provide a high-resolution representation of the extracellular field dynamics. Here, we study the most robust, highest-amplitude oscillons recorded in actively behaving male rats, which underlie the traditional θ-waves. The resemblances between θ-oscillons and the conventional θ-waves are manifested primarily at the ballpark level—mean frequencies, mean amplitudes, and bandwidths. In addition, both hippocampal and cortical oscillons exhibit a number of intricate, behavior-attuned, transient properties that suggest a new vantage point for understanding the θ-rhythms’ structure, origins and functions. In particular, we demonstrate that oscillons are frequency-modulated waves, with speed-controlled …

Pseudomonas Aeruginosa Exoy Enzymatic Activity Inhibits Exos-Induced Caspase-3/7 Activation But Not Cytotoxicity In Pmvecs, Connor Holm

Poster Presentations

Pseudomonas aeruginosa (P. aer.) is the most common cause of ventilator associated pneumonia (VAP) in ICU patients. Different combinations of exoenzymes (S, T, Y, and U) are found in P. aer. strains. ExoY is most often associated with VAP in ICU patients. ExoY infection of pulmonary microvascular endothelial cells (PMVECs) induces cell rounding but does not activate intracellular caspase-3/7 or cause cell death. ExoS and ExoT infection of epithelial cells leads to caspase-3/7 dependent cell death. Previous studies using epithelial cells show that ExoY alleviates the cytotoxic effects of ExoS and ExoT. Here, we sought to determine whether ExoY inhibits …

Exploring The Role Of Lysine Acetylation During Biofilm Formation In Bacillus Subtilis, Jennifer Nguyen, Briana Ericka Reid, Valerie Carabetta

Rowan-Virtua Research Day

Biofilms are structured communities of bacterial cells encased in a self-produced extracellular matrix, composed of polysaccharides, extracellular DNA, and proteins. Bacteria in a biofilm pose significant challenges in healthcare due to their resistance to disinfectants and tolerance to antibiotics. In some species, histone-like proteins were found to be important structural components of the biofilm. Nε-Lysine acetylation is a widespread post-translational modification (PTM) in bacteria, which can alter a protein’s function. The histone-like protein HBsu in Bacillus subtilis is acetylated at seven sites in vivo. We hypothesized that the acetylation state of HBsu may alter biofilm structure or the genetic programming, …