Molecular cloning and characterization of the afa-7 and afa-8 gene clusters encoding afimbrial adhesins in Escherichia coli strains associated with diarrhea or septicemia in calves.

ABSTRACT: The afa gene clusters, which encode proteins involved in adhesion to epithelial cells, from Escherichia coli strains associated with urinary and intestinal infections in humans have been characterized. Pathogenic isolates of bovine and porcine origin that possess afa-related sequences have recently been described. We report in this work the cloning and characterization of the afa-7 and afa-8 gene clusters from bovine isolates. Hybridization and sequencing experiments revealed that despite similarity in genetic organization, the afa-7 and afa-8 genes, and the well-characterized afa-3 operon expressed by human-pathogenic isolates, correspond to three different members of the afa family of gene clusters. However, like the afa-3 gene cluster, both the afa-7 and afa-8 gene clusters were found t

SUBMITTER: Lalioui L 

PROVIDER: S-EPMC96852 | biostudies-literature | 1999 Oct

REPOSITORIES: biostudies-literature