Emergence of High-Level Colistin Resistance in an Acinetobacter baumannii Clinical Isolate Mediated by Inactivation of the Global Regulator H-NS.

ABSTRACT: Colistin is a crucial last-line drug used for the treatment of life-threatening infections caused by multidrug-resistant strains of the Gram-negative bacterium Acinetobacter baumannii However, colistin-resistant A. baumannii isolates can still be isolated following failed colistin therapy. Resistance is most often mediated by the addition of phosphoethanolamine (pEtN) to lipid A by PmrC, following missense mutations in the pmrCAB operon encoding PmrC and the two-component signal transduction system PmrA/PmrB. We recovered a pair of A. baumannii isolates from a single patient before (6009-1) and after (6009-2) failed colistin treatment. These strains displayed low and very high levels of colistin resistance (MICs, 8 to 16 μg/ml and 128 μg/ml), respectively. To un

SUBMITTER: Deveson Lucas D 

PROVIDER: S-EPMC6021671 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature