A putative RND-type efflux pump, H239_3064, contributes to colistin resistance through CrrB in Klebsiella pneumoniae.

ABSTRACT:

Background

Colistin is one of the last-resort antibiotics used to treat carbapenem-resistant Klebsiella pneumoniae infection. Our previous studies indicated that clinical strains encoding CrrB with amino acid substitutions exhibited higher colistin resistance (MICs ≥512 mg/L) than did colistin-resistant strains encoding mutant MgrB, PmrB or PhoQ.

Objectives

CrrAB may regulate another unknown mechanism(s) contributing to colistin resistance, besides modifications of LPS with 4-amino-4-deoxy-l-arabinose and phosphoethanolamine.

Methods

To identify these potential unknown mechanism(s), a transposon mutant library of A4528 crrB(N141I) was constructed. Loci that might contribute to colistin resistance and were regulated by crrB were confirmed by deletion and complementatio

SUBMITTER: Cheng YH 

PROVIDER: S-EPMC5961088 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature