RT Journal Article SR Electronic(1) A1 Vidal, Maricel A1 Prado, Valeria A1 Whitlock, Gregory C. A1 Solari, Aldo A1 Torres, Alfredo G. A1 Vidal, Roberto M.YR 2008 T1 Subtractive hybridization and identification of putative adhesins in a Shiga toxin-producing eae-negative Escherichia coli JF Microbiology, VO 154 IS 12 SP 3639 OP 3648 DO https://doi.org/10.1099/mic.0.2008/021212-0 PB Microbiology Society, SN 1465-2080, AB Adherence to epithelial cells by specific adhesins is a characteristic of Shiga toxin-producing Escherichia coli (STEC) strains. The eae-encoded protein intimin is the main adhesin implicated in intestinal colonization in vivo. We recently showed that STEC strains isolated in Chile displayed a wide variety of adhesins; here we demonstrate that some of these STEC strains are eae-negative and still adhere to epithelial cells at a level 100-fold higher than enterohaemorrhagic E. coli (EHEC) O157 : H7 prototype strain EDL933. This phenotype is associated with the presence of adherence factors different from the intimin protein. Subtractive hybridization between EHEC EDL933 and STEC eae-negative strain 472-1 was used to identify regions implicated in adhesion. In addition to the saa gene, we identified 18 specific genes in STEC 472-1, 16 of which had nucleotide identity to Salmonella ST46 phage genes; the two remaining ones shared identity to a gene encoding a hypothetical protein of uropathogenic E. coli. The DNA sequence of the STEC 472-1 psu-int region identified five open reading frames with homology to phage genes. We constructed mutant strains in the saa gene and the psu-int region to study the participation of these genes in the adherence to epithelial cells and our results demonstrated that STECΔsaa and STECΔpsu-int mutants displayed a 10-fold decrease in adherence as compared to the STEC 472-1 wild-type strain. Overall, our results suggest that STEC strain 472-1 adheres to epithelial cells in an eae-independent matter and that saa and psu-int participate in this adhesion process., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/mic.0.2008/021212-0