Genomic Insights into Intrinsic and Acquired Drug Resistance Mechanisms in Achromobacter xylosoxidans

Abstract

ABSTRACTAchromobacter xylosoxidansis an opportunistic pathogen known to be resistant to a wide range of antibiotics; however, the knowledge about the drug resistance mechanisms is limited. We used a high-throughput sequencing approach to sequence the genomes of theA. xylosoxidanstype strain ATCC 27061 and a clinical isolate,A. xylosoxidansX02736, and then we used different bioinformatics tools to analyze the drug resistance genes in these bacteria. We obtained the complete genome sequence forA. xylosoxidansATCC 27061 and the draft sequence for X02736. We predicted a total of 50 drug resistance-associated genes in the type strain, including 5 genes for β-lactamases and 17 genes for efflux pump systems; these genes are also conserved among otherA. xylosoxidansgenomes. In the clinical isolate, except for the conserved resistance genes, we also identified several acquired resistance genes carried by a new transposon embedded in a novel integrative and conjugative element. Our study provides new insights into the intrinsic and acquired drug resistance mechanisms inA. xylosoxidans, which will be helpful for better understanding the physiology ofA. xylosoxidansand the evolution of antibiotic resistance in this bacterium.