Characterization ofqnrB-Like Genes in Citrobacter Species of the American Type Culture Collection

Abstract

ABSTRACTAmong five American Type Culture Collection (ATCC)Citrobacterstrains,qnrB60inCitrobacter freundiiATCC 6879, an isolate from the preantibiotic era, andqnrB61inCitrobacter braakiiATCC 51113T, a type strain belonging to theC. freundiicomplex, were identified. Meanwhile, a truncatedqnrB-like pseudogene was identified inC. freundiiATCC 8090Tand ATCC 43864. NoqnrB-like sequence was found inCitrobacter koseriATCC 27028T. These findings underscore the close relationship between this species andqnrB.