Copyright © 1994, American Society for Microbiology The eaeB Gene of Enteropathogenic Escherichia coli Is Necessary for Signal Transduction in Epithelial Cells

An enteropathogenic Escherichia coli mutant carrying an internal deletion in the eaeB gene (UMD864) was unable to activate epithelial cell signals, including tyrosine phosphorylation, cytoskeletal rearrangements, and the release of inositol phosphates, indicating that the eaeB locus encodes a product that is involved in stimulating signals in epithelial cells. Enteropathogenic Escherichia coli (EPEC) is a leading cause of infantile diarrhea, mediated through bacterium-host cell contact, in developing countries (11). Following initial attach-ment, EPEC exploits host cell signaling pathways to promote intimate adherence. The resulting attaching and effacing lesion is characterized by a loss of microvilli and the rearrangement of host cell tyrosine-phosphorylated and cytoskeletal proteins (6, 9, 13). A mutant was recently constructed by creating a deletion in the eaeB gene, which is located approximately 5 kb downstream of the eaeA gene on the EPEC chromosome (4). The AeaeB deletion mutant (UMD864) is unable to attac