Medicine and Health Sciences Commons^™

An Investigation Into The Prevalence Of Vancomycin-Resistant Enterococci Within An Irish Hospital, Dylan Casey

International Undergraduate Journal of Health Sciences

Vancomycin-resistant enterococci (VRE) are well-recognised nosocomial pathogens that pose a significant threat to public health. Associated with poorer clinical outcomes than their vancomycin-sensitive counterparts, the prevalence of VRE in Ireland has increased in recent times, with the European Antimicrobial Resistance Surveillance Network reporting that out of 29 countries, Ireland demonstrated the highest rates of vancomycin resistance among invasive Enterococcus faecium isolates between 2011 and 2014 (2011; 34.9%, 2012; 44.0%, 2013; 42.7%, 2014; 45.1%). Herein, we investigate VRE prevalence in the Mercy University Hospital (MUH) – an acute care hospital in southern Ireland. A total of 21 first-time VRE infections were …

Eliminating Contamination In Umbilical Cord Blood Culture Sampling For Early-Onset Neonatal Sepsis., Vilmaris Quinones Cardona, Vanessa Lowery, David Cooperberg, Endla K Anday, Alison J Carey

Department of Pediatrics Faculty Papers

Introduction: Despite the advantages of umbilical cord blood culture (UCBC) use for diagnosis of early onset sepsis (EOS), contamination rates have deterred neonatologists from its widespread use. We aimed to implement UCBC collection in a level III neonatal intensive care unit (NICU) and apply quality improvement (QI) methods to reduce contamination in the diagnosis of early onset sepsis. Methods: Single-center implementation study utilizing quality improvement methodology to achieve 0% contamination rate in UCBC samples using the Plan-Do-Study-Act (PDSA) model for improvement. UCBC was obtained in conjunction with peripheral blood cultures (PBC) in neonates admitted to the NICU due to maternal …

The Mrna-Lnp Platform's Lipid Nanoparticle Component Used In Preclinical Vaccine Studies Is Highly Inflammatory, Sonia Ndeupen, Zhen Qin, Sonya Jacobsen, Aurélie Bouteau, Henri Estanbouli, Botond Z. Igyártó

Department of Microbiology and Immunology Faculty Papers

Vaccines based on mRNA-containing lipid nanoparticles (LNPs) are a promising new platform used by two leading vaccines against COVID-19. Clinical trials and ongoing vaccinations present with varying degrees of protection levels and side effects. However, the drivers of the reported side effects remain poorly defined. Here we present evidence that Acuitas' LNPs used in preclinical nucleoside-modified mRNA vaccine studies are highly inflammatory in mice. Intradermal and intramuscular injection of these LNPs led to rapid and robust inflammatory responses, characterized by massive neutrophil infiltration, activation of diverse inflammatory pathways, and production of various inflammatory cytokines and chemokines. The same dose of …

Evaluation Of Stratified Antibiograms For Use In Laboratory And Antimicrobial Stewardship, Linsey Donner

Theses & Dissertations

Antibiograms are critical for choosing empiric antimicrobial therapy. Cumulative antibiograms, which aggregate susceptibility data, can mask differences within specific patient subsets or clinical syndromes. This dissertation was done to determine if antibiotic susceptibilities showed substantial differences when comparing stratified antibiograms to cumulative antibiograms.

Antibiotic susceptibility data was retrospectively obtained from Nebraska Medicine January 1, 2017 – December 31, 2019 for Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus, and Enterococcus faecalis. The University of Nebraska Medical Center’s web antibiogram clinical decision support tool was used to export the data. Bacteria-antibiotic susceptibility rates of stratified antibiograms …

Characterizing And Overcoming Resistance To Aminomethylspectinomycins In Gram-Negative Bacteria, Nisha Das

Theses and Dissertations (ETD)

Spectinomycin (SPC) is a broad-spectrum aminocyclitol antibiotic. Its use in agriculture has led to widespread resistance in enteric bacteria, necessitating the development of more effective analogs. Aminomethyl spectinomycins (amSPC) are modified spectinomycins with increased potency against many bacterial species. These species include Legionella pneumophila, which harbors a chromosomally encoded aminoglycoside modifying enzyme (AME). In this study, we follow up on this observation and examine the extent to which the amSPCs are substrates for AMEs through adenylation (ANTs) and phosphorylation (APH). APH(9)-Ia and ANT(3")(9) were expressed in E. coli BL21(DE3) and purified using the Ni-affinity chromatography. The ability of AMEs to …

Sars-Cov-2 Induces Robust Germinal Center Cd4 T Follicular Helper Cell Responses In Rhesus Macaques, Yashavanth Shaan Lakshmanappa, Sonny R. Elizaldi, Jamin W. Roh, Brian A. Schmidt, Timothy D. Carroll, Kourtney D. Weaver, Justin C. Smith, Anil Verma, Jesse D. Deere, Joseph Dutra, Mars Stone, Sergej Franz, Rebecca Lee Sammak, Katherine J. Olstad, J. Rachel Reader, Zhong Min Ma, Nancy K. Nguyen, Jennifer Watanabe, Jodie Usachenko, Ramya Immareddy

School of Graduate Studies Faculty Publications

CD4 T follicular helper (Tfh) cells are important for the generation of durable and specific humoral protection against viral infections. The degree to which SARS-CoV-2 infection generates Tfh cells and stimulates the germinal center (GC) response is an important question as we investigate vaccine induced immunity against COVID-19. Here, we report that SARS-CoV-2 infection in rhesus macaques, either infused with convalescent plasma, normal plasma, or receiving no infusion, resulted in transient accumulation of pro-inflammatory monocytes and proliferating Tfh cells with a Th1 profile in peripheral blood. CD4 helper cell responses skewed predominantly toward a Th1 response in blood, lung, and …

Genital Chlamydia Infection Is Influenced By The Female Sex Hormones Estrogen And Progesterone In Vivo, Amy Gail Gravitte

Electronic Theses and Dissertations

Chlamydia is the most common bacterial sexually transmitted infection in the United States and worldwide. It often goes unnoticed due to lack of symptoms and left untreated it can ascend the female genital tract to cause sequelae like pelvic inflammatory disease and irreversible tubal infertility. In reproductive-aged women, female sex hormones estrogen (E2) and progesterone (P4) concentrations fluctuate during the menstrual cycle and are influenced by hormonal contraceptives and hormone replacement therapy. E2 and P4 influence genital Chlamydia infection in women and mice, but these multifactorial interactions are not entirely mapped out. The complex interplay of E2 and P4 with …

Moerv29 Promotes Apoplastic Effector Secretion Contributing To Virulence Of The Rice Blast Fungus Magnaporthe Oryzae, Bin Qian, Xiaotong Su, Ziyuan Ye, Xinyu Liu, Muxing Liu, Danyu Shen, Han Chen, Haifeng Zhang, Ping Wang, Zhengguang Zhang

School of Medicine Faculty Publications

During plant-pathogenic fungi and host plants interactions, numerous pathogen-derived proteins are secreted resulting in the activation of the unfolded protein response (UPR) pathway. For efficient trafficking of secretory proteins, including those important in disease progression, the cytoplasmic coat protein complex II (COPII) exhibits a multifunctional role whose elucidation remains limited. Here, we discovered that the COPII cargo receptor MoErv29 functions as a target of MoHac1, a previously identified transcription factor of the UPR pathway. In Magnaporthe oryzae, deletion of MoERV29 severely affected the vegetative growth, conidiation and biotrophic invasion of the fungus in susceptible rice hosts. We demonstrated that MoErv29 …

Lysergic Acid Diethylamide Induces Increased Signalling Entropy In Rats’ Prefrontal Cortex, Aurora Savino, Charles D. Nichols

School of Graduate Studies Faculty Publications

Psychedelic drugs are gaining attention from the scientific community as potential new compounds for the treatment of psychiatric diseases such as mood and substance use disorders. The 5-HT2A receptor has been identified as the main molecular target, and early studies pointed to an effect on the expression of neuroplasticity genes. Analysing RNA-seq data from the prefrontal cortex of rats chronically treated with lysergic acid diethylamide (LSD), we describe the psychedelic-induced rewiring of gene co-expression networks, which become less centralised but more complex, with an overall increase in signalling entropy typical of highly plastic systems. Intriguingly, signalling entropy mirrors, at the …

A Strategy To Detect Emerging Non-Delta Sars-Cov-2 Variants With A Monoclonal Antibody Specific For The N501 Spike Residue, Rama Devudu Puligedda, Fetweh H Al-Saleem, Christoph Wirblich, Chandana Devi Kattala, Marko Jović, Laura Geiszler, Himani Devabhaktuni, Giora Z Feuerstein, Matthias J. Schnell, Markus Sack, Lawrence L Livornese, Scott K Dessain

Department of Microbiology and Immunology Faculty Papers

Efforts to control SARS-CoV-2 have been challenged by the emergence of variant strains that have important implications for clinical and epidemiological decision making. Four variants of concern (VOCs) have been designated by the Centers for Disease Control and Prevention (CDC), namely, B.1.617.2 (delta), B.1.1.7 (alpha), B.1.351 (beta), and P.1 (gamma), although the last three have been downgraded to variants being monitored (VBMs). VOCs and VBMs have shown increased transmissibility and/or disease severity, resistance to convalescent SARS-CoV-2 immunity and antibody therapeutics, and the potential to evade diagnostic detection. Methods are needed for point-of-care (POC) testing to rapidly identify these variants, protect …

Cancer Vaccines And Immunotherapy For Tumor Prevention And Treatment, Jagmohan Singh, Wilbur Bowne, Adam E. Snook

Kimmel Cancer Center Faculty Papers

In this editorial, we highlight articles published in this Special Issue of Vaccines on "Cancer Vaccines and Immunotherapy for Tumor Prevention and Treatment", recent developments in the field of cancer vaccines, and the potential for immunotherapeutic combinations in cancer care. This issue covers important developments and progress being made in the cancer vaccine field and possible future directions for exploring new technologies to produce optimal immune responses against cancer and expand the arena of prophylactic and therapeutic cancer vaccines for the treatment of this deadly disease.

The Sulfur Microbial Diet Is Associated With Increased Risk Of Early-Onset Colorectal Cancer Precursors, Long H. Nguyen, Yin Cao, Jinhee Hur, Raaj S. Mehta, Daniel R. Sikavi, Yiqing Wang, Wenjie Ma, Kana Wu, Mingyang Song, Edward L. Giovannucci, Eric B. Rimm, Walter C. Willett, Wendy S. Garrett, Jacques Izard, Curtis Huttenhower, Andrew T. Chan

Food for Health: Publications

Background & Aims: Diet may contribute to the increasing incidence of colorectal cancer (CRC) before age 50 (early-onset CRC). Microbial metabolism of dietary sulfur produces hydrogen sulfide (H2S), a gastrointestinal carcinogen that cannot be easily measured at scale. As a result, evidence supporting its role in early neoplasia is lacking. Methods: We evaluated long-term adherence to the sulfur microbial diet, a dietary index defined a priori based on increased abundance of 43 bacterial species involved with sulfur metabolism, with risk of CRC precursors among 59,013 individuals who underwent lower endoscopy in the Nurses’ Health Study II (1991–2015), a prospective cohort …

Attenuated Bacteria Potentiate The Outcome Of Immunotherapy With Pd-L1 Blockade In A Pre-Clinical Model Of Colorectal Cancer, Besan Haytham Mohammad Al-Saafeen

Theses

After more than a century of investigation, it has become evident that cancer development and progression occur at the expense of a dysfunctional immune system. This realization has ushered cancer immunotherapy as a new modality of treatment. In the last decade, the use of immune checkpoint inhibitors to treat cancer patients resulted in unprecedented and durable clinical benefits. However, the response rate in many cancers remains rather modest, with colorectal cancer being at the lower end of the spectrum. Previous work from our laboratory demonstrated the efficacy of using attenuated bacteria as immunomodulatory anti-cancer agents. The current study investigated the …

Advancing Rna Virus Discovery And Biology With Whole Genome Sequencing, Mariah Katherine Taylor

Theses and Dissertations (ETD)

Two RNA virus families that pose a threat to human and animal health are Hantaviridae and Coronaviridae. These RNA viruses which originate in wildlife continue and will continue to cause disease, and hence, it is critical that scientific research define the mechanisms as to how these viruses spillover and adapt to new hosts to become endemic. One gap in our ability to define these mechanisms is the lack of whole genome sequences for many of these viruses. To address this specific gap, I developed a versatile amplicon-based whole-genome sequencing (WGS) approach to identify viral genomes of hantaviruses and severe acute …

Longitudinal Shotgun Metagenomic Analysis Of The Vaginal Microbiome During The Onsetof Bacterial Vaginosis, John W. Lammons, Jacob H. Elnagger, Evelyn Toh, Amy Dong, Kristal J. Aaron, Meng Luo, Ashutosh Tamhane, Elliot J. Lefkowitz, David E. Nelson, Christina A. Muzny, Christopher M. Taylor

Medical Student Research Poster Symposium

Introduction: Bacterial Vaginosis (BV) is a common disorder associated with the vaginal microbiome characterized by the displacement of lactobacillus with an overgrowth of anaerobes. Symptomatic cases can be associated with Pelvic Inflammatory Disease (PID), complications with pregnancy, and greater susceptibility to sexually transmitted infections. In cases where antibiotics are needed to treat BV, recurrence commonly occurs within 3 months to a year. Despite the prevalence of BV, the specific mechanism associated with the onset is unclear. In this pilot study we utilized shotgun metagenomics to identify the discrete changes occurring in the vaginal microbiome leading up to the onset of …

Intestinal Dysbiosis – A New Treatment Target In The Prevention Of Colorectal Cancer, Florinela-Andrada Dumitru, Sergiu Ioan Micu, Roxana Emanuela Popoiag, Marilena Musat, Andreea Daniela Caloian, Valentin Calu, Vlad Denis Constantin, Daniela Gabriela Balan, Cornelia Nitipir, Florin Enache

Journal of Mind and Medical Sciences

The gastrointestinal microbiome contains at least 100 trillion microorganisms (bacteria, viruses, fungi), whose distribution varies from the mouth to the rectum spatially and temporally throughout one's lifetime. The microbiome benefits from advancing research due to its major role in human health. Studies indicate that its functions are immunity, metabolic processes and mucosal barrier. The disturbances of these functions, dysbiosis, influence physiology, lead to diabetes, inflammatory bowel disease, obesity and colon tumorigenesis. The third most common form of cancer, colorectal cancer, is the result of many factors and genes, and although the link between dysbiosis and this type of cancer is …

Output Consistency Scale To Standardize Ostomate Output Description In Clinical Practice And Studies, Lisa Whisenhunt, Linda Xu, Fan Yang, Jacques Izard

Food for Health: Publications

Stool descriptors have become popular due to the large diffusion of the Bristol Stool Form Scale (BSFS) via clinical studies, clinical trials, and social media. The applications have been numerous and centered around standardization of terminology that can be used by health care professionals and patients alike, as well as individuals interested in their wellness and the associated partners in the wellness industry. For a portion of the population, the digestive content is rerouted to an external manufactured pouch or bag, making the use of the BSFS visual descriptors of stool difficult. From day one post-resection surgery, ostomates are challenged …

Prion Disease: A Challenging Diagnosis, Jeffrey F. Spindel, Anita M. Fletcher, William T. Smith, Rodrigo Cavallazzi

The University of Louisville Journal of Respiratory Infections

Introduction: Human prion diseases are a group of rare encephalopathies resulting in rapidly progressive dementia and ultimately death. While there are no effective treatments for any form of prion disease, prompt and efficient diagnosis is essential to prevent the spread of the self-propagating protein, which may occur through aerosols, and avoid unnecessary or invasive testing. Diagnosis relies largely on physical examination, with many nonspecific findings, and laboratory testing, which has wide ranges of reported accuracy and high false positive rates with diseases such as Alzheimer’s dementia.

Methods: Patients who underwent testing for prion disease were retrospectively identified from the electronic …

Microbial Influence On Alzheimer's Disease, Ashley N. Hamby

The Cardinal Edge

No abstract provided.

Development Of A Recombinant Vaccine Against Human Onchocerciasis., David Abraham, John Graham-Brown, Darrick Carter, Sean A. Gray, Jessica A. Hess, Benjamin L. Makepeace, Sara Lustigman

Department of Microbiology and Immunology Faculty Papers

Introduction: Human onchocerciasis caused by the filarial nematode parasite Onchocerca volvulus remains a major cause of debilitating disease infecting millions primarily in Sub-Saharan Africa. The development of a prophylactic vaccine, along with mass drug administration, would facilitate meeting the goal of onchocerciasis elimination by 2030.

Areas covered: Models used to study immunity to Onchocerca include natural infection of cattle with Onchocerca ochengi and O. volvulus infective third-stage larvae implanted within diffusion chambers in mice. A vaccine, comprised of two adjuvanted recombinant antigens, induced protective immunity in genetically diverse mice suggesting that it will function similarly in diverse human populations. These …

Endophytes Of Brazilian Medicinal Plants With Activity Against Phytopathogens, Jucélia Iantas, Daiani Cristina Savi, Renata Da Silva Schibelbein, Sandriele Aparecida Noriler, Beatriz Marques Assad, Guilherme Dilarri, Henrique Ferreira, Jürgen Rohr, Jon S. Thorson, Khaled A. Shaaban, Chirlei Glienke

Pharmaceutical Sciences Faculty Publications

Plant diseases caused by phytopathogens are responsible for significant crop losses worldwide. Resistance induction and biological control have been exploited in agriculture due to their enormous potential. In this study, we investigated the antimicrobial potential of endophytic fungi of leaves and petioles of medicinal plants Vochysia divergens and Stryphnodendron adstringens located in two regions of high diversity in Brazil, Pantanal, and Cerrado, respectively. We recovered 1,304 fungal isolates and based on the characteristics of the culture, were assigned to 159 phenotypes. One isolate was selected as representative of each phenotype and studied for antimicrobial activity against phytopathogens. Isolates with better …

Assesment Of Antibiotic Resistant Gene Expression In Clinical Isolates Of Pseudomonas Aeruginosa, Dustin Esmond

Biology Theses

Increasing prevalence of nosocomial infections by antimicrobial resistant pathogens resulting in higher mortality rates and financial burden is of great concern. Pseudomonas aeruginosa represents one of six highly virulent “ESKAPE” pathogens that exhibit considerable intrinsic drug resistance as well as mechanisms for acquiring further resistance. As many of these mechanisms are regulated through gene expression, we sought to identify regulatory strategies and patterns at play in 23 clinical isolates collected from Baku, Azerbaijan and Tyler, Texas, USA. Real-time quantitative polymerase chain reaction was performed on six gene targets implicated in resistance and contrasted with antibiotic phenotypes. We found AmpC cephalosporinase …

Multiple Autonomous Cell Death Suppression Strategies Ensure Cytomegalovirus Fitness, Pratyusha Mandal, Lynsey Nagrani, Liliana Hernandez, Anita Louise Mccormick, Christopher Dillon, Heather Koehler, Linda Roback, Emad S Alnemri, Douglas Green, Edward Mocarski

Department of Biochemistry and Molecular Biology Faculty Papers

Programmed cell death pathways eliminate infected cells and regulate infection-associated inflammation during pathogen invasion. Cytomegaloviruses encode several distinct suppressors that block intrinsic apoptosis, extrinsic apoptosis, and necroptosis, pathways that impact pathogenesis of this ubiquitous herpesvirus. Here, we expanded the understanding of three cell autonomous suppression mechanisms on which murine cytomegalovirus relies: (i) M38.5-encoded viral mitochon-drial inhibitor of apoptosis (vMIA), a BAX suppressor that functions in concert with M41.1-encoded viral inhibitor of BAK oligomerization (vIBO), (ii) M36-encoded viral inhibitor of caspase-8 activation (vICA), and (iii) M45-encoded viral inhibitor of RIP/RHIM activation (vIRA). Following infection of bone marrow-derived macrophages, the virus initially …

Loss Of N1-Methylation Of G37 In Trna Induces Ribosome Stalling And Reprograms Gene Expression, Isao Masuda, Jae-Yeon Hwang, Thomas Christian, Sunita Maharjan, Fuad Mohammad, Howard Gamper, Allen R. Buskirk, Ya-Ming Hou

Department of Biochemistry and Molecular Biology Faculty Papers

N¹-methylation of G37 is required for a subset of tRNAs to maintain the translational reading-frame. While loss of m¹G37 increases ribosomal +1 frameshifting, whether it incurs additional translational defects is unknown. Here, we address this question by applying ribosome profiling to gain a genome-wide view of the effects of m¹G37 deficiency on protein synthesis. Using E coli as a model, we show that m¹G37 deficiency induces ribosome stalling at codons that are normally translated by m¹G37-containing tRNAs. Stalling occurs during decoding of affected codons at the ribosomal A site, indicating …

Targeting Human Langerin Promotes Hiv-1 Specific Humoral Immune Responses., Jérôme Kervevan, Aurélie Bouteau, Juliane S Lanza, Adele Hammoudi, Sandra Zurawski, Mathieu Surenaud, Lydie Dieudonné, Marion Bonnet, Cécile Lefebvre, Hakim Hocini, Romain Marlin, Aurélie Guguin, Barbara Hersant, Oana Hermeziu, Elisabeth Menu, Christine Lacabaratz, Jean-Daniel Lelièvre, Gerard Zurawski, Véronique Godot, Sandrine Henri, Botond Z. Igyártó, Yves Levy, Sylvain Cardinaud

Department of Microbiology and Immunology Faculty Papers

The main avenue for the development of an HIV-1 vaccine remains the induction of protective antibodies. A rationale approach is to target antigen to specific receptors on dendritic cells (DC) via fused monoclonal antibodies (mAb). In mouse and non-human primate models, targeting of skin Langerhans cells (LC) with anti-Langerin mAbs fused with HIV-1 Gag antigen drives antigen-specific humoral responses. The development of these immunization strategies in humans requires a better understanding of early immune events driven by human LC. We therefore produced anti-Langerin mAbs fused with the HIV-1 gp140z Envelope (αLC.Env). First, we show that primary skin human LC and …

Targeted Oral Delivery Of Paclitaxel Using Colostrum-Derived Exosomes, Raghuram Kandimalla, Farrukh Aqil, Sara S. Alhakeem, Jeyaprakash Jeyabalan, Neha Tyagi, Ashish Agrawal, Jun Yan, Wendy Spencer, Subbarao Bondada, Ramesh C. Gupta

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Lung cancer is the leading cause of cancer-related deaths worldwide. Non-small-cell lung cancer (NSCLC) is the most common type accounting for 84% of all lung cancers. Paclitaxel (PAC) is a widely used drug in the treatment of a broad spectrum of human cancers, including lung. While efficacious, PAC generally is not well tolerated and its limitations include low aqueous solubility, and significant toxicity. To overcome the dose-related toxicity of solvent-based PAC, we utilized bovine colostrum-derived exosomes as a delivery vehicle for PAC for the treatment of lung cancer. Colostrum provided higher yield of exosomes and could be loaded with higher …

Inhibitory Molecules Pd-1, Cd73 And Cd39 Are Expressed By Cd8+ T Cells In A Tissue-Dependent Manner And Can Inhibit T Cell Responses To Stimulation, Corinne J. Smith, Christopher M. Snyder

Department of Microbiology and Immunology Faculty Papers

The salivary gland is an important tissue for persistence and transmission of multiple viruses. Previous work showed that salivary gland tissue-resident CD8+ T cells elicited by viruses were poorly functional ex vivo. Using a model of persistent murine cytomegalovirus (MCMV) infection, we now show that CD8+ T cells in the salivary gland and other non-lymphoid tissues of mice express multiple molecules associated with T cell exhaustion including PD-1, CD73 and CD39. Strikingly however, these molecules were expressed independently of virus or antigen. Rather, PD-1-expressing T cells remained PD-1+ after migration into tissues regardless of infection, while CD73 was activated on …

Accumulation Of Succinyl Coenzyme A Perturbs The Methicillin-Resistant Staphylococcus Aureus (Mrsa) Succinylome And Is Associated With Increased Susceptibility To Beta-Lactam Antibiotics, Christopher Campbell, Claire Fingleton, Merve S. Zeden, Emilio Bueno, Laura A Gallagher, Dhananjay Shinde, Jong-Sam Ahn, Heather M. Olson, Thomas L. Fillmore, Joshua N. Adkins, Fareha Razvi, Kenneth W. Bayles, Paul D. Fey, Vinai Chittezham Thomas, Felipe Cava, Geremy C. Clair, James P. O'Gara

Journal Articles: Pathology and Microbiology

Penicillin binding protein 2a (PBP2a)-dependent resistance to β-lactam antibiotics in methicillin-resistant Staphylococcus aureus (MRSA) is regulated by the activity of the tricarboxylic acid (TCA) cycle via a poorly understood mechanism. We report that mutations in sucC and sucD, but not other TCA cycle enzymes, negatively impact β-lactam resistance without changing PBP2a expression. Increased intracellular levels of succinyl coenzyme A (succinyl-CoA) in the sucC mutant significantly perturbed lysine succinylation in the MRSA proteome. Suppressor mutations in sucA or sucB, responsible for succinyl-CoA biosynthesis, reversed sucC mutant phenotypes. The major autolysin (Atl) was the most succinylated protein in the proteome, …

Sars-Cov-2 Viral Proteins Nsp1 And Nsp13 Inhibit Interferon Activation Through Distinct Mechanisms, Christine Vazquez, Sydnie E Swanson, Seble G Negatu, Mark Dittmar, Jesse Miller, Holly Ramage, Sara Cherry, Kellie A Jurado

Department of Microbiology and Immunology Faculty Papers

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a devastating global pandemic, infecting over 43 million people and claiming over 1 million lives, with these numbers increasing daily. Therefore, there is urgent need to understand the molecular mechanisms governing SARS-CoV-2 pathogenesis, immune evasion, and disease progression. Here, we show that SARS-CoV-2 can block IRF3 and NF-κB activation early during virus infection. We also identify that the SARS-CoV-2 viral proteins NSP1 and NSP13 can block interferon activation via distinct mechanisms. NSP1 antagonizes interferon signaling by suppressing host mRNA translation, while NSP13 downregulates interferon and NF-κB promoter signaling by limiting TBK1 …

The Prospect Of Nanoparticle Systems For Modulating Immune Cell Polarization During Central Nervous System Infection, Lee E. Korshoj, Wen Shi, Bin Duan, Tammy Kielian

Journal Articles: Pathology and Microbiology

The blood-brain barrier (BBB) selectively restricts the entry of molecules from peripheral circulation into the central nervous system (CNS) parenchyma. Despite this protective barrier, bacteria and other pathogens can still invade the CNS, often as a consequence of immune deficiencies or complications following neurosurgical procedures. These infections are difficult to treat since many bacteria, such as Staphylococcus aureus, encode a repertoire of virulence factors, can acquire antibiotic resistance, and form biofilm. Additionally, pathogens can leverage virulence factor production to polarize host immune cells towards an anti-inflammatory phenotype, leading to chronic infection. The difficulty of pathogen clearance is magnified by …