Medical Microbiology Commons^™

Advancing Peptide-Based Vaccines Against Candida: A Comparative Perspective On Liposomal And Synthetic Formulations, Hong Xin

School of Graduate Studies Faculty Publications

The growing threat of multidrug-resistant fungal pathogens, especially Candida auris, has underscored the need for effective antifungal vaccines. This commentary highlights recent advances in peptide-based vaccination using the SNAP (Spontaneous Nanoliposome Antigen Presentation) platform, focusing on the FM-SNAP vaccine, a bivalent liposomal formulation targeting the surface-expressed peptides fructose bisphosphate aldolase (Fba) and methionine synthase (Met6). Compared to earlier constructs such as MP12, FM-SNAP achieves superior immunogenicity and long-lasting protection at lower antigen doses. It elicits balanced Th1/Th2 cytokine responses and demonstrates durable efficacy in both immunocompetent and complement-deficient mouse models. The platform's compatibility with clinically approved adjuvants (MPLA and QS-21), …

Investigating Bacterial Vaginosis Pathogenesis Using Peptide Nucleic Acid-Fluorescence In Situ Hybridization With A Focus On The Roles Of Gardnerella Species, Prevotella Bivia, And Fannyhessea Vaginae, Sheridan D. George, Megan H. Amerson-Brown, Lúcia G.V. Sousa, Tyler M. Carter, Alexa H. Rinehart, Ashleigh N. Riegler, Sixto M. Leal, Kristal J. Aaron, Jiaying Hao, Ashutosh Tamhane, Chaoling Dong, John W. Lammons, Jacob H. Elnaggar, Keonte J. Graves, Paweł Łaniewski, Melissa M. Herbst-Kralovetz, Christopher M. Taylor, Nuno Cerca, Christina A. Muzny

School of Graduate Studies Faculty Publications

Background. Bacterial vaginosis (BV) is a vaginal dysbiosis characterized by polymicrobial communities of BV-associated bacteria (BVAB) adhered to the vaginal epithelium. Despite decades of research, its etiology remains unknown. We aimed to investigate BV biofilm formation over time among women who developed incident BV (iBV) using peptide nucleic acid-fluorescence in situ hybridization (PNA-FISH), focusing on 3 key BVAB (Gardnerella species, Prevotella bivia, and Fannyhessea vaginae). Methods. Heterosexual, nonpregnant women ages 18–45 with optimal vaginal microbiota were enrolled to self-collect twice-daily vaginal specimens for 60 days. iBV was defined as a Nugent score of 7–10 on ≥ 4 consecutive specimens. For …

Enhancing Preparedness: A Genetic Study Of Sar-Cov-2 And Other Microbial Public Health Threats In Wastewater From A College Town, Christian N. Hutchinson

Master's Theses

Problem

The SARS-CoV-2 (COVID-19) pandemic revealed both the systemic vulnerabilities of our healthcare system as well as the importance of timely, localized data for informing public health responses. Traditional testing approaches were essential but often failed to capture the full extent of viral spread, especially in those with mild or asymptomatic conditions that relied on at home testing. This underreporting hindered effective allocation of resources and made developing effective intervention strategies difficult. We also realized the potential for wastewater surveillance to be applied to tracking antimicrobial resistance gene markers. Taken together, this approach should have important implications for improving public …

Bcg Vaccine-Induced Innate And Adaptive Pulmonary Immunity Correlating With Protective Efficacy Against Mycobacterium Tuberculosis In The Lungs, Mayank Khanna, Alistair J. Ramsay

School of Graduate Studies Faculty Publications

Background/Objectives: Effective prophylaxis for Mycobacterium tuberculosis (Mtb) requires greater understanding of immune correlates of protection. With renewed interest in BCG as an Mtb vaccine, particularly via the intravenous (IV) route, our objective was to characterize both innate and adaptive immune correlates of vaccine-induced pulmonary immunity as potential biomarkers for protective efficacy in a murine model of Mtb infection. Methods: Mice were given BCG via different routes and some boosted with recombinant virus constructs encoding Mtb Ag85B. Responding innate lymphoid cell (ILC) populations, T cells and B cells were analyzed by fluorescence activated cell sorting (FACS) for surface markers and by …

The Swib Domain-Containing Dna Topoisomerase I Of Chlamydia Trachomatis Mediates Dna Relaxation, Li Shen, Abigail R. Swoboda, Caitlynn Diggs, Shomita Ferdous, Andrew Terrebonne, Amanda Santos, Noel Wolf, Luis Lorenzo Carvajal, Guangming Zhong, Scot P. Ouellette, Yuk Ching Tse-Dinh

School of Graduate Studies Faculty Publications

Chlamydia trachomatis has a DNA topoisomerase I with a unique C-terminal domain (CTD) homologous to eukaryotic SWIB domains. This study focused on determining the function of the SWIB domain-containing TopA from C. trachomatis (CtTopA). We demonstrated that, despite the lack of sequence similarity at the CTDs between CtTopA and TopA from Escherichia coli (EcTopA), full-length CtTopA removed negative DNA supercoils in vitro and complemented the growth defect of a topA mutant of E. coli. CtTopA is less processive in DNA relaxation than EcTopA in dose-response and time course studies. An antibody generated against the SWIB domain of CtTopA specifically recognized …

Multivalvular Native Valve E. Coli Endocarditis, Madison Baker, Jose Reyes, Natasha Singh, Samir Shah, Rohail A. Baig, Justin Nistico

Advances in Clinical Medical Research and Healthcare Delivery

E. coli is a rare cause of infective endocarditis. This report describes an 81-year-old-woman with a history of aortic stenosis and recurrent urinary tract infections who presented in sepsis secondary to E. coli urinary tract infection which was complicated by multivalvular infective endocarditis of the aortic and tricuspid native valves identified on transesophageal echocardiogram (TEE). The patient was managed medically with ceftriaxone, and resolution of both vegetations was seen on TEE without the need for cardiothoracic surgery. Literature review did not yield prior cases of multivalvular E. coli endocarditis.

Egg White Hydrolysate In Hypertension: A Mechanistic Investigation Of Gut Microbiota Dependent And Independent Pathways, Emerson David Nolasco

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Cardiovascular diseases are one of the leading causes of mortality worldwide in which hypertension is a risk factor. Present pharmacological interventions require long-term adherence to the therapy and are often associated with undesirable side effects. Moreover, treatments have overlooked the role of the microbiome in the development of hypertension. Egg white hydrolysate (EWH) has exhibited antihypertensive properties with potential to be used as a natural alternative for the prevention and management of hypertension. However, EWH peptide’s effect on the gut microbiome remains yet to be elucidated. Studies have described that a portion of the ingested protein can remain undigested as …

Engineered Bifidobacterium Strains Colonization At Tumor Sites: A Novel Approach To The Delivery Of Cancer Treatments, Rhea Amonkar, Ashley Ann Uy, Pablo Ramirez, Harina Patel, Jae Jin Jeong, Nicole Oyinade Shoyele, Vidhi Vaghela, Ashakumary Lakshmikuttyamma

Department of Pharmacology, Physiology, and Cancer Biology Faculty Papers

Bacteria-mediated cancer therapy represents a novel and promising strategy for targeted drug delivery to solid tumors. Multiple studies have demonstrated that various Bifidobacterium species can selectively colonize the hypoxic microenvironments characteristic of solid tumors. Leveraging this property, Bifidobacterium has been explored as a delivery vector for a range of anti-cancer approaches such as immunotherapy, nanoformulated chemotherapeutics, and gene therapy. Notably, anti-angiogenic genes such as endostatin and tumstatin have been successfully delivered to colorectal tumors using Bifidobacterium infantis and Bifidobacterium longum, respectively. Additionally, Bifidobacterium bifidum has been employed to transport doxorubicin and paclitaxel nanoparticles to breast and lung tumor sites. …

Dietary Nitrogen And Its Role In The Gut Microbiome And Inflammatory Bowel Disease: A Narrative Review, Matthew Herrera, Lauri O. Byerley

School of Medicine Faculty Publications

In recent years, gut microbiota has emerged as a critical regulator of gastrointestinal health and disease, with its role in inflammatory bowel disease (IBD)—including Crohn’s disease and ulcerative colitis—being particularly significant. Among the many factors influencing the gut microbiota, dietary components such as fibers, fats, and polyphenols have received substantial attention. However, nitrogen-containing compounds, such as amino acids, nitrates, urea, and even nucleic acids, such as purines, remain underexplored despite their integral role in shaping microbial ecology, host metabolism, and immune responses. Some of these compounds are metabolized by gut bacteria into bioactive molecules such as short-chain fatty acids, ammonia, …

The Effect Of Temperature For Producing Thayer-Martin Agar Media Using Sheep Blood On Neisseria Gonorrhoeae Growth With Various Inoculums, Ika Ningsih, Kayla Adyapratista Sumadiyo

Indonesian Journal of Medical Chemistry and Bioinformatics

Neisseria gonorrhoeae is a Gram-negative bacterium in the form of diplococci that infects mucous membranes through direct inoculation, is fastidious, and requires special media for growth because it is susceptible to heating and dryness, so it cannot survive long outside its host. Thayer-Martin agar media is a selective culture medium for the diagnosis of Neisseria gonorrhoeae bacterial infections enriched with sheep blood. The purpose of this study was to determine the optimum temperature for various temperature variations of making Thayer-Martin agar when mixing with sheep blood, compared to the temperature according to the manufacturer's procedure. Determining this ideal temperature may …

Distinct Echinocandin Responses Of Candida Albicans And Candida Auris Cell Walls Revealed By Solid-State Nmr, Malitha C. Dickwella Widanage, Kalpana Singh, Jizhou Li, Jayasubba Reddy Yarava, Faith J. Scott, Yifan Xu, Neil A.R. Gow, Frederic Mentink-Vigier, Ping Wang, Frederic Lamoth, Tuo Wang

School of Graduate Studies Faculty Publications

Invasive candidiasis affects 1.6 million people annually, with high mortality among immunocompromised and hospitalized patients. Echinocandins are frontline antifungals, but rising resistance limits their efficacy. Here, we show that Candida albicans and multidrug-resistant Candida auris share a conserved cell wall architecture yet differ markedly in their adaptive responses to echinocandins. Solid-state NMR reveals that both species possess a rigid inner layer of tightly associated chitin microfibrils and β−1,3-glucans, supported by a flexible matrix of β−1,6-glucans and additional β−1,3-glucans. Outer mannan fibrils rely on α−1,2-linked sidechains to maintain contact with the inner wall. In both species, caspofungin rigidifies β−1,6-glucans and mannan …

A Lysosomal Surveillance Response To Stress Extends Healthspan, Terytty Yang Li, Arwen W Gao, Rendan Yang, Yu Sun, Yuxuan Lei, Xiaoxu Li, Lin Chen, Yasmine J Liu, Rachel N Arey, Kimberly Morales, Raya B Liu, Wenzheng Wang, Ang Zhou, Tong-Jin Zhao, Weisha Li, Amélia Lalou, Qi Wang, Tanes Lima, Riekelt H Houtkooper, Johan Auwerx

Faculty, Staff and Students Publications

Lysosomes are cytoplasmic organelles central for the degradation of macromolecules to maintain cellular homoeostasis and health. However, how lysosomal activity can be boosted to counteract ageing and ageing-related diseases remains elusive. Here we reveal that silencing specific vacuolar H+-ATPase subunits (for example, vha-6), which are essential for intestinal lumen acidification in Caenorhabditis elegans, extends lifespan by ~60%. This longevity phenotype can be explained by an adaptive transcriptional response typified by induction of a set of transcripts involved in lysosomal function and proteolysis, which we termed the lysosomal surveillance response (LySR). LySR activation is characterized by boosted lysosomal activity …

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 …

Environmental Screening For Multidrug Resistant (Mdr) Organisms In The Surgical Ward Of An Irish Tertiary Referral Hospital., Sinead A. Fahy, Sinéad Fahy

ORBioM (Open Research BioSciences Meeting)

The aim of the current study was to determine the prevalence of Multidrug Resistant Organisms (MDRO) colonisation on a surgical ward of an acute tertiary hospital. MDRO determination was conducted on a patient-occupied surgical ward over a 6-month period. The screen included sink, and shower drains in bathrooms and sinks of multi-bedded and single-occupied rooms. Swabs were cultured on chromogenic agar to enable detection of methicillin resistant Staphylococcus aureus (MRSA), Carbapenemase producing enterobacterales (CPE), Vancomycin Resistant Enterococci (VRE) and Extended spectrum beta-lactamase (ESBL). Suspect resistant organisms were confirmed using NG-Carba 5 (NG Biotech, Guipry, France) lateral flow tests, Vitek 2.0 …

Inactivation Of The Fusobacterium Nucleatum Rnf Complex Reduces Fada-Mediated Amyloid Formation And Tumor Development, Timmie A Britton, Ju Huck Lee, Chungyu Chang, Aadil H Bhat, Yi-Wei Chen, Rusul Mohammed Ali, Chenggang Wu, Asis Das, Hung Ton-That

Faculty, Staff and Student Publications

The Gram-negative anaerobe Fusobacterium nucleatum is an oral oncobacterium that promotes colorectal cancer (CRC) development with the amyloid-forming cell surface adhesin FadA integral to CRC tumorigenesis. We describe here molecular genetic studies uncovering a novel mode of metabolic regulation of FadA-mediated tumor formation by a highly conserved respiratory enzyme known as the Rnf complex. First, we show that genetic disruption of Rnf, via rnfC deletion, significantly reduces the level of fadA transcript, accompanied by a near-complete abolishment of the precursor form of FadA (pFadA), reduced assembly of FadA at the mature cell pole, and severe defects in the osmotic stress-induced …

Characterization Of Immunogenicity Of Hiv Mrna Vaccine In Humanized Mice, Omoyeni Precious Adejare

Biotechnology Theses

Human Immunodeficiency Virus (HIV) remains a leading global cause of mortality. Despite decades of research, a definitive cure or an effective vaccine for HIV infection has yet to be discovered. The major target for HIV vaccine development is the envelope (Env) trimeric protein that is responsible for host cell attachment and fusion. This comprises gp120 and the transmembrane gp41. Gp140, a truncated form of gp160(full envelope trimer) lacks the transmembrane and cytoplasmic domains of gp41, closely mimics the native HIV envelope has been shown to enhance the induction of broadly neutralizing antibodies (BnAbs) when used as protein vaccine in previous …

Monoclonal Antibodies Targeting Candida Disrupt Biofilms And Inhibit Growth Across Global Clinical Isolates, Jonothan Rosario-Colon, Karen Eberle, Hong Xin

School of Graduate Studies Faculty Publications

Candida species are a major cause of severe fungal infections, particularly in immunocompromised individuals and hospitalized patients. Among these, Candida auris stands out as an emerging “superbug”, responsible for life-threatening bloodstream infections with mortality rates up to 60%. This multidrug-resistant, hospital-acquired pathogen has been declared a serious global health threat, complicating effective treatment and increasing mortality risks. Our research has identified universal monoclonal antibodies (mAbs) targeting Candida albicans cell wall epitopes, which are highly homologous to those in other pathogenic Candida species, including C. auris. Passive transfer of mAbs—C3.1 (anti-β-1,2-mannotriose) and 9F2 (anti-phosphoglycerate kinase 1)—significantly extended survival and improved fungal …

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, …

Pseudomonas Aeruginosa Exoenzyme Y Enzymatic Activity Inhibits Exoenzyme S-Induced Caspase Activation But Not Cytotoxicity In Pulmonary Microvascular Endothelial Cells, Connor Holm

Honors Theses

Pseudomonas aeruginosa (P. aeruginosa) is the most common cause of ventilator-associated pneumonia in intensive care unit patients. P. aeruginosa utilizes a type III secretion system that injects exoenzymes U, S, T, and/or Y into the host cell cytosol. A majority of clinically isolated P. aeruginosa strains express ExoY often in combination with ExoU and ExoT, or ExoS and ExoT. Host signaling mechanisms in response to intoxication with individual exoenzymes have been extensively studied, yet little is known about host cell response to co-intoxication. In this study, pulmonary microvascular endothelial cells (PMVECs) were infected with P. aeruginosa strains expressing different combinations …