Molecular characterization of ESBL-producing Escherichia coli isolates from hospital- and community-acquired infections in NW Mexico

Abstract We investigated the molecular characteristics of ESBL-producing E. coli (ESBL-P Ec) isolates from two hospitals and community settings in Ciudad Obregon, Sonora, Mexico. Between 2011 and 2014, thirty-seven ESBL-P Ec isolates were collected. The major encoded ESBL was the bla CTX-M-15 gene (97%); followed by 13.5% of the bla SHV-12 gene, and 5.5% encoded the bla TLA-1 gene. The PMQR gene aac(6´)-Ib-cr was detected in 97% of the isolates and the qnrB gene, in one isolate. The ESBL-P Ec isolates corresponded to phylogenetic group B2, ST131. Our results highlight the dissemination of ESBL-P Ec isolates in northwest Mexico (Ciudad Obregon, Sonora).