Insertion Sequence ISAba11Is Involved in Colistin Resistance and Loss of Lipopolysaccharide in Acinetobacter baumannii

Abstract

ABSTRACTInfections caused byAcinetobacter baumanniiare of increasing concern, largely due to the multidrug resistance of many strains. Here we show that insertion sequence ISAba11movement can result in inactivation of theA. baumanniilipid A biosynthesis geneslpxAandlpxC, resulting in the complete loss of lipopolysaccharide production and high-level colistin resistance.