Complete deletion of the ramR gene in an in vitro-selected mutant of Klebsiella pneumoniae overexpressing the AcrAB efflux pump

摘要

In Klebsiella pneumoniae, overexpression of nonspecific efflux pumps causes low-level cross-resistance to beta-lactams (mainly cefoxitin) and to antibiotics belonging to other families, such as quinolones, chloramphenicol, and tetracycline. Among these efflux systems, the pump AcrAB seems to be the one most involved in antibiotic resistance in Enterobacteriaceae, including K. pneumoniae.