Global dissemination of optrA-mediated linezolid resistance in enterococci

Abstract

Objectives: Acquired resistance to last-line linezolid has emerged in Enterococcus spp. and can be conferred by the optrA gene. Here, we study the global genomic context of optrA in E. faecalis and E. faecium, to understand its dissemination pattern. Methods: We identified 565 enterococcal genomes from NCBI and 86 optrA-containing enterococcal plasmids from the plasmid database, PLSDB. We characterized the plasmid replication and antimicrobial resistance genes of optrA-containing plasmids and the plasmid pangenome. To identify prevalent optrA genetic contexts, we mapped the genomes against PLSDB plasmid and transposon Tn6674 (prevalent in E. faecalis) sequences using minimap2. Results: A gre..