RT Journal Article T1 Polymyxin resistance caused by mgrB inactivation is not associated with significant biological cost in Klebsiella pneumoniae A1 Cannatelli, Antonio A1 Santos López, Alfonso A1 Giani, Tommaso A1 González Zorn, Bruno A1 Rossolini, Gian Maria AB The inactivation of the mgrB gene, which encodes a negative-feedback regulator of the PhoPQ signaling system, was recently shown to be a common mutational mechanism responsible for acquired polymyxin resistance among carbapenemase-producing Klebsiella pneumoniae strains from clinical sources. In this work, we show that mgrB mutants can easily be selected in vitro from different K. pneumoniae lineages, and mgrB inactivation is not associated with a significant biological cost. PB American Society for Microbiology SN 1098-6596 YR 2015 FD 2015-05 LK https://hdl.handle.net/20.500.14352/24678 UL https://hdl.handle.net/20.500.14352/24678 LA eng NO Unión Europea. FP7 DS Docta Complutense RD 6 abr 2025