Submitted to: Meeting Abstract
Publication Type: Abstract only
Publication Acceptance Date: 2/27/2006
Publication Date: 8/13/2006
Citation: Faith, N., Kathariou, S., Neudeck, B., Luchansky, J.B., Czuprynski, C. 2006. The role of l. monocytogenes serotype 4b antigens in the pathogenesis of listeriosis. [abstract]. International Association for Food Protection's Annual Meeting. P4-56. pg. 77. Interpretive Summary:
Technical Abstract: Most large outbreaks of listeriosis are associated with serotype 4b strains of Listeria monocytogenes. In this study we investigated the role of gtcA, a gene which regulates glycosylation of teichoic acid, in the pathogenesis of listeriosis. We found that two different serotype 4b mutants of gtcA, which lack glucose or galactose residues on their teichoic acid, were significantly less virulent than their wild type parents when inoculated intragastrically into A/J mice. To gain some knowledge of whether the effect of gtcA was manifested only in the gastrointestinal tract, we also performed experiments in which this environment was circumvented by inoculating mice intravenously. We found that both the gtcA mutants exhibited lower virulence than the parent strain in the liver, and one of the strains also caused less severe infection in the spleens of i.v. inoculated A/J mice. In addition, both gtcA mutants of L. monocytogenes were less able to invade, and multiplied to a lower final number of intracellular bacilli in a human intestinal epithelial cell line (Caco-2 cells) in vitro, than did their respective wild type parent strains. These data suggest a role for gtcA in the pathogenesis of listeriosis. Future experiments will determine the effect of gtcA on the ability of L. monocytogenes to grow on ready to eat meat products, and mechanisms by which gtcA affects serotype 4b antigen expression and virulence.