Research Publications (Food Safety)

Enteropathogenic Escherichia coli (EPEC)-induced diarrhea is often associated with disruption of intestinal epithelial tight junctions. Although studies have shown alterations in the expression and localization of bicellular tight junction proteins during EPEC infections, little is known about whether tricellular tight junction proteins (tTJs) are affected. Using Caco-2 cell monolayers, we investigated if EPEC is capable of targeting the tTJ protein tricellulin.

Our recent study demonstrated that virulent Coxiella burnetii Nine Mile phase I (NMI) is capable of infecting and replicating within peritoneal B1a cells and that B1a cells play an important role in host defense against C. burnetii infection in mice. However, it remains unknown if avirulent Nine Mile phase II (NMII) can infect and replicate in B1a cells and whether NMI and NMII can differentially interact with B1a cells.

Salmonella species utilize type III secretion systems (T3SSs) to translocate effectors into the cytosol of mammalian host cells, subverting cell signaling and facilitating the onset of gastroenteritis. In this study, we compared a draft genome assembly of Salmonella enterica subsp. salamae strain 3588/07 against the genomes of S. enterica subsp. enterica serovar Typhimurium strain LT2 and Salmonella bongori strain 12419. S. enterica subsp.

At present, there is no vaccine for enterotoxigenic Escherichia coli (ETEC), an important cause of diarrheal illness. Nevertheless, recent microbial pathogenesis studies have identified a number of molecules produced by ETEC that contribute to its virulence and are novel antigenic targets to complement canonical vaccine approaches. EtpA is a secreted two-partner adhesin that is conserved within the ETEC pathovar.

Enoyl-acyl carrier protein reductase catalyzes the last step in each elongation cycle of type II bacterial fatty acid synthesis and is a key regulatory protein in bacterial fatty acid synthesis. Genes of the facultative intracellular pathogen Listeria monocytogenes encode two functional enoyl-acyl carrier protein isoforms based on their ability to complement the temperature-sensitive growth phenotype of Escherichia coli strain JP1111 [fabI(Ts)].

Intestinal epithelial cells provide an important colonization niche for Salmonella enterica serovar Typhimurium during gastrointestinal infections. In infected epithelial cells, a subpopulation of S. Typhimurium bacteria damage their internalization vacuole, leading to escape from the Salmonella-containing vacuole (SCV) and extensive proliferation in the cytosol.

Brucella species are facultative intracellular bacteria that cause brucellosis, a chronic debilitating disease significantly impacting global health and prosperity. Much remains to be learned about how Brucella spp. succeed in sabotaging immune host cells and how Brucella spp. respond to environmental challenges. Multiple types of bacteria employ the prokaryotic second messenger cyclic di-GMP (c-di-GMP) to coordinate responses to shifting environments.

Campylobacter jejuni is a helix-shaped enteric bacterial pathogen and a common cause of gastroenteritis. We recently developed a mouse model for this human pathogen utilizing the SIGIRR-deficient mouse strain, which exhibits significant intestinal inflammation in response to intestinal C. jejuni infection. In the current study, this mouse model was used to define whether C.

Neutrophils are essential components of immunity and are rapidly recruited to infected or injured tissue. Upon their activation, neutrophils release granules to the cell's exterior, through a process called degranulation. These granules contain proteins with antimicrobial properties that help combat infection.

Yersinia enterocolitica evades the immune response by injecting Yersinia outer proteins (Yops) into the cytosol of host cells. YopH is a tyrosine phosphatase critical for Yersinia virulence. However, the mucosal immune mechanisms subverted by YopH during in vivo orogastric infection with Y. enterocolitica remain elusive. The results of this study revealed neutrophil recruitment to Peyer's patches (PP) after infection with a YopH-deficient mutant strain (Y. enterocolitica yopH). While the Y.

Vibrio cholerae is an intestinal pathogen that causes the diarrheal disease cholera. Colonization of the intestine depends upon the expression of genes that allow V. cholerae to overcome host barriers, including low pH, bile acids, and the innate immune system. ToxR is a major contributor to this process. ToxR is a membrane-spanning transcription factor that coordinates gene expression in response to environmental cues.