Interspecies Dissemination of the bla Gene Encoding PER-1 Extended-Spectrum β-Lactamase

PER-1 extended-spectrum β-lactamase-producing Gram-negative bacilli are resistant to oxyimino-cephalosporins. However, the bla(PER-1) gene has never been reported in Klebsiella pneumoniae. Here, we studied interspecies dissemination of the bla(PER-1) gene by horizontal transfer of Tn1213 among Acinetobacter baumannii, Pseudomonas aeruginosa, and K. pneumoniae. In a K. pneumoniae clinical isolate, the bla(PER-1) gene was located on a 150-kbp incompatibility group A/C plasmid.