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Research Publications (Food Safety)

This page tracks research articles published in national and international peer-reviewed journals. Recent articles are available ahead of print and searchable by Journal, Article Title, and Category. Research publications are tracked across six categories: Bacterial Pathogens, Chemical Contaminants, Natural Toxins, Parasites, Produce Safety, and Viruses. Articles produced by USDA Grant Funding Agencies (requires login) and FDA Grant Funding Agencies (requires login) are also tracked in Scopus.

Displaying 76 - 100 of 261

  1. A Point Mutation in carR Is Involved in the Emergence of Polymyxin B-Sensitive Vibrio cholerae O1 El Tor Biotype by Influencing Gene Transcription

    • Infection and Immunity
    • Antimicrobial peptides play an important role in host defense against Vibrio cholerae. Generally, the V. cholerae O1 classical biotype is polymyxin B (PB) sensitive and El Tor is relatively resistant. Detection of classical biotype traits like the production of classical cholera toxin and PB sensitivity in El Tor strains has been reported in recent years, including in the devastating Yemen cholera outbreak during 2016-2018.

      • Vibrio
      • Bacterial pathogens
  2. B Cells Inhibit CD4+ T Cell-Mediated Immunity to Brucella Infection in a Major Histocompatibility Complex Class II-Dependent Manner

    • Infection and Immunity
    • Brucella spp. are facultative intracellular bacteria notorious for their ability to induce a chronic, and often lifelong, infection known as brucellosis. To date, no licensed vaccine exists for prevention of human disease, and mechanisms underlying chronic illness and immune evasion remain elusive. We and others have observed that B cell-deficient mice challenged with Brucella display reduced bacterial burden following infection, but the underlying mechanism has not been clearly defined.

      • Bacterial pathogens
  3. Interaction of Brucella abortus with Osteoclasts: a Step toward Understanding Osteoarticular Brucellosis and Vaccine Safety

    • Infection and Immunity
    • Osteoarticular disease is a frequent complication of human brucellosis. Vaccination remains a critical component of brucellosis control, but there are currently no vaccines for use in humans, and no in vitro models for assessing the safety of candidate vaccines in reference to the development of bone lesions currently exist. While the effect of Brucella infection on osteoblasts has been extensively evaluated, little is known about the consequences of osteoclast infection.

      • Bacterial pathogens
  4. Bread Feeding Is a Robust and More Physiological Enteropathogen Administration Method Compared to Oral Gavage

    • Infection and Immunity
    • Oral administration is a preferred model for studying infection by bacterial enteropathogens such as Yersinia spp. In the mouse model, the most frequent method for oral infection consists of oral gavage with a feeding needle directly introduced in the animal stomach via the esophagus. In this study, we compared needle gavage to bread feeding as an alternative mode of bacterial administration.

      • Bacterial pathogens
      • Yersinia
  5. The Dynll1-Cox4i1 Complex Regulates Intracellular Pathogen Clearance via Release of Mitochondrial Reactive Oxygen Species

    • Infection and Immunity
    • Cellular membrane proteins are a critical part of the host defense mechanisms against infection and intracellular survival of Listeria monocytogenes. The complex spatiotemporal regulation of bacterial infection by various membrane proteins has been challenging to study. Here, using mass spectrometry analyses, we depicted the dynamic expression landscape of membrane proteins upon L. monocytogenes infection in dendritic cells.

      • Bacterial pathogens
      • Listeria monocytogenes
  6. Atypical Salmonella enterica Serovars in Murine and Human Macrophage Infection Models

    • Infection and Immunity
    • Nontyphoidal Salmonella species are globally disseminated pathogens and are the predominant cause of gastroenteritis. The pathogenesis of salmonellosis has been extensively studied using in vivo murine models and cell lines, typically challenged with Salmonella enterica serovar Typhimurium. Although S.

      • Bacterial pathogens
      • Salmonella
  7. Antibiotic Degradation by Commensal Microbes Shields Pathogens

    • Infection and Immunity
    • The complex bacterial populations that constitute the gut microbiota can harbor antibiotic resistance genes (ARGs), including those encoding β-lactamase enzymes (BLA), which degrade commonly prescribed antibiotics such as ampicillin. The prevalence of such genes in commensal bacteria has been increased in recent years by the wide use of antibiotics in human populations and in livestock.

      • Bacterial pathogens
      • Listeria monocytogenes
  8. Vibrio cholerae Virulence Activator ToxR Regulates Manganese Transport and Resistance to Reactive Oxygen Species

    • Infection and Immunity
    • Like many other pathogens, Vibrio cholerae, the causative agent of cholera, can modulate its gene expression to combat stresses encountered in both aquatic and host environments, including stress posed by reactive oxygen species (ROS). We previously reported that the virulence activator AphB in V. cholerae is involved in ROS resistance. In this study, we found that another key virulence regulator, ToxR, was important for V. cholerae resistance to hydrogen peroxide.

      • Vibrio
      • Bacterial pathogens
  9. Vibrio cholerae OmpR Represses the ToxR Regulon in Response to Membrane Intercalating Agents That Are Prevalent in the Human Gastrointestinal Tract

    • Infection and Immunity
    • Multidrug efflux systems belonging to the resistance-nodulation-division (RND) superfamily are ubiquitous in Gram-negative bacteria. RND efflux systems are often associated with multiple antimicrobial resistance and also contribute to the expression of diverse bacterial phenotypes including virulence, as documented in the intestinal pathogen Vibrio cholerae, the causative agent of the severe diarrheal disease cholera. Transcriptomic studies with RND efflux-negative V.

      • Vibrio
      • Bacterial pathogens
  10. Twin-Arginine Translocation System Is Involved in Citrobacter rodentium Fitness in the Intestinal Tract

    • Infection and Immunity
    • The twin-arginine translocation (Tat) system is involved in not only a wide array of cellular processes but also pathogenesis in many bacterial pathogens; thus, this system is expected to become a novel therapeutic target to treat infections. To the best of our knowledge, involvement of the Tat system has not been reported in the gut infection caused by Citrobacter rodentium. Here, we studied the role of Tat in C.

      • Bacterial pathogens
  11. The Invasion Plasmid Antigen J (IpaJ) from Salmonella Inhibits NF-{kappa}B Activation by Suppressing I{kappa}B{alpha} Ubiquitination

    • Infection and Immunity
    • Salmonella enterica serovar Pullorum is the pathogen of pullorum disease, which leads to severe economic losses in many developing countries. In contrast to the strong inflammatory response induced by Salmonella enterica serovar Typhimurium and Salmonella enterica serovar Enteritidis, S. Pullorum causes systemic infection with little inflammation.

      • Salmonella
      • Bacterial pathogens
  12. Regulation of OmpA Translation and Shigella dysenteriae Virulence by an RNA Thermometer

    • Infection and Immunity
    • RNA thermometers are cis-acting riboregulators that mediate the posttranscriptional regulation of gene expression in response to environmental temperature. Such regulation is conferred by temperature-responsive structural changes within the RNA thermometer that directly result in differential ribosomal binding to the regulated transcript. The significance of RNA thermometers in controlling bacterial physiology and pathogenesis is becoming increasingly clear.

      • Shigella
      • Bacterial pathogens
  13. Mechanical Stimuli Affect Escherichia coli Heat-Stable Enterotoxin-Cyclic GMP Signaling in a Human Enteroid Intestine-Chip Model

    • Infection and Immunity
    • Modeling host-pathogen interactions with human intestinal epithelia using enteroid monolayers on permeable supports (such as Transwells) represents an alternative to animal studies or use of colon cancer-derived cell lines. However, the static monolayer model does not expose epithelial cells to mechanical forces normally present in the intestine, including luminal flow and serosal blood flow (shear force) or peristaltic forces.

      • Bacterial pathogens
  14. Major Histocompatibility Complex Class II-Restricted, CD4+ T Cell-Dependent and -Independent Mechanisms Are Required for Vaccine-Induced Protective Immunity against Coxiella burnetii

    • Infection and Immunity
    • To understand the role of major histocompatibility complex class I (MHC-I) and MHC-II in vaccine-mediated protection against Coxiella burnetii, we evaluated the protective efficacy of a formalin-inactivated C. burnetii Nine Mile phase I vaccine (PIV) in β2-microglobulin-deficient (B2m KO) and MHC-II-deficient (MHC-II KO) mice. Vaccination reduced disease severity in wild-type (WT) and B2m KO mice but failed to reduce bacterial burden in MHC-II KO mice.

      • Bacterial pathogens
  15. Whipworm Infection Promotes Bacterial Invasion, Intestinal Microbiota Imbalance, and Cellular Immunomodulation

    • Infection and Immunity
    • Infections with Trichuris trichiura are among the most common causes of intestinal parasitism in children worldwide, and the diagnosis is based on microscopic egg identification in the chronic phase of the infection. During parasitism, the adult worm of the trichurid nematode maintains its anterior region inserted in the intestinal mucosa, which causes serious damage and which may open access for gut microorganisms through the intestinal tissue.

  16. Biogenesis of the Spacious Coxiella-Containing Vacuole Depends on Host Transcription Factors TFEB and TFE3

    • Infection and Immunity
    • Coxiella burnetii is an obligate intracellular bacterial pathogen that replicates inside the lysosome-derived Coxiella-containing vacuole (CCV). To establish this unique niche, C. burnetii requires the Dot/Icm type IV secretion system (T4SS) to translocate a cohort of effector proteins into the host cell, which modulate multiple cellular processes. To characterize the host-pathogen interactions that occur during C.

      • Bacterial pathogens
  17. The Nonmevalonate Pathway of Isoprenoid Biosynthesis Supports Anaerobic Growth of Listeria monocytogenes

    • Infection and Immunity
    • Isoprenoids are an essential and diverse class of molecules, present in all forms of life, that are synthesized from an essential common precursor derived from either the mevalonate pathway or the nonmevalonate pathway. Most bacteria have one pathway or the other, but the Gram-positive, facultative intracellular pathogen Listeria monocytogenes is unusual because it carries all the genes for both pathways.

      • Listeria monocytogenes
      • Bacterial pathogens
  18. Brucella abortus Depends on L-Serine Biosynthesis for Intracellular Proliferation

    • Infection and Immunity
    • l-Serine is a nonessential amino acid and a key intermediate in several relevant metabolic pathways. In bacteria, the major source of l-serine is the phosphorylated pathway, which comprises three enzymes: d-3-phosphoglycerate dehydrogenase (PGDH; SerA), phosphoserine amino transferase (PSAT; SerC), and l-phosphoserine phosphatase (PSP; SerB).

      • Bacterial pathogens
  19. The Host GTPase Arf1 and Its Effectors AP1 and PICK1 Stimulate Actin Polymerization and Exocytosis To Promote Entry of Listeria monocytogenes

    • Infection and Immunity
    • Listeria monocytogenes is a foodborne bacterium that causes gastroenteritis, meningitis, or abortion. Listeria induces its internalization (entry) into some human cells through interaction of the bacterial surface protein InlB with its host receptor, the Met tyrosine kinase. InlB and Met promote entry through stimulation of localized actin polymerization and exocytosis. How actin cytoskeletal changes and exocytosis are controlled during entry is not well understood.

      • Listeria monocytogenes
      • Bacterial pathogens
  20. Salmonella enterica Requires Lipid Metabolism Genes To Replicate in Proinflammatory Macrophages and Mice

    • Infection and Immunity
    • To survive and replicate during infection, pathogens utilize different carbon and energy sources depending on the nutritional landscape of their host microenvironment. Salmonella enterica serovar Typhimurium is an intracellular bacterial pathogen that occupies diverse cellular niches. While it is clear that Salmonella Typhimurium requires access to glucose during systemic infection, data on the need for lipid metabolism are mixed.

      • Bacterial pathogens
      • Salmonella
  21. Human Enteric Defensin 5 Promotes Shigella Infection of Macrophages

    • Infection and Immunity
    • Human α-defensins are 3- to 5-kDa disulfide-bridged peptides with a multitude of antimicrobial activities and immunomodulatory functions. Recent studies show that human enteric α-defensin 5 (HD5), a host defense peptide important for intestinal homeostasis and innate immunity, aids the highly infectious enteropathogen Shigella in breaching the intestinal epithelium in vitro and in vivo.

      • Bacterial pathogens
      • Shigella
  22. Salmonella enterica Serovar Typhimurium Uses PbgA/YejM To Regulate Lipopolysaccharide Assembly during Bacteremia

    • Infection and Immunity
    • Salmonella enterica serovar Typhimurium (S. Typhimurium) relies upon the inner membrane protein PbgA to enhance outer membrane (OM) integrity and promote virulence in mice. The PbgA transmembrane domain (residues 1 to 190) is essential for viability, while the periplasmic domain (residues 191 to 586) is dispensable. Residues within the basic region (residues 191 to 245) bind acidic phosphates on polar phospholipids, like for cardiolipins, and are necessary for salmonella OM integrity. S.

      • Bacterial pathogens
      • Salmonella
  23. A Loss-of-Function Mutation in the Integrin Alpha L (Itgal) Gene Contributes to Susceptibility to Salmonella enterica Serovar Typhimurium Infection in Collaborative Cross Strain CC042

    • Infection and Immunity
    • Salmonella is an intracellular bacterium found in the gastrointestinal tract of mammalian, avian, and reptilian hosts. Mouse models have been extensively used to model in vivo distinct aspects of human Salmonella infections and have led to the identification of several host susceptibility genes. We have investigated the susceptibility of Collaborative Cross strains to intravenous infection with Salmonella enterica serovar Typhimurium as a model of human systemic invasive infection.

      • Bacterial pathogens
      • Salmonella
  24. Transcriptional and Pathological Host Responses to Coinfection with Virulent or Attenuated Mycoplasma gallisepticum and Low-Pathogenic Avian Influenza A Virus in Chickens

    • Infection and Immunity
    • The avian pathogen Mycoplasma gallisepticum, the etiological agent of chronic respiratory disease in chickens, exhibits enhanced pathogenesis in the presence of a copathogen such as low-pathogenic avian influenza virus (LPAIV). To further investigate the intricacies of this copathogenesis, chickens were monoinfected or coinfected with either virulent M.

      • Viruses
  25. Mutation of the Transcriptional Regulator YtoI Rescues Listeria monocytogenes Mutants Deficient in the Essential Shared Metabolite 1,4-Dihydroxy-2-Naphthoate (DHNA)

    • Infection and Immunity
    • Listeria monocytogenes, a Gram-positive, facultative intracellular pathogen, survives and replicates in the cytosol of host cells. Synthesis of 1,4-dihydroxy-2-naphthoate (DHNA), an intermediate of menaquinone biosynthesis, is essential for cytosolic survival of L. monocytogenes independent from its role in respiration. Here, we demonstrate that DHNA is essential for virulence in a murine model of listeriosis due to both respiration-dependent and -independent functions.

      • Bacterial pathogens
      • Listeria monocytogenes