The gene products of Listeria monocytogenes induced specifically during rabbit infection

Abstract

Listeria monocytogenes is a Gram-positive, facultative, intracellular bacterium that can cause severe food-borne illness referred to as listeriosis in both humans and animals. This study has developed a rabbit model for the identification of L. monocytogenes gene products specifically induced during infection by constructing a L. monocytogenes protein expression library followed by differential immunoscreening with two kinds of antisera, one (RaL) from rabbits infected with viable bacteria, and the other (RaK) from animals immunized with heatkilled bacteria. This strategy led to the discovery of several L. monocytogenes proteins, including three members (InlA, InlD, and InlC2) of the internalin family, in which InlA and InlB are known bacterial virulence factors, and five novel proteins of unknown function (designated IspWei, IspLing, IspYu, IspMin, and IspLin, respectively). Library screening and Western blots showed that these proteins reacted only with RaL, indicating that they are specifically induced during infection. (Abstract shortened by UMI.)