Evolution of a 72-kb cointegrant, conjugative multiresistance plasmid from early community-associated methicillin-resistant Staphylococcus aureus isolates.

Evolution of a 72-kb cointegrant, conjugative multiresistance plasmid from early community-associated methicillin-resistant Staphylococcus aureus isolates. Antimicrob Agents Chemother. 2019 Sep 09;: Authors: Yui Eto K, Firth N, Davis AM, Kwong SM, Krysiak M, Lee YT, O'Brien FG, Grubb WB, Coombs GW, Bond CS, Ramsay JP Abstract Horizontal transfer of plasmids encoding antimicrobial-resistance and virulence determinants has been instrumental in Staphylococcus aureus evolution, including the emergence of community-associated methicillin-resistant S. aureus (CA-MRSA). In the early 1990s the first CA-MRSA isolated in Western Australia (WA), WA-5, encoded cadmium, tetracycline and penicillin-resistance genes on plasmid pWBG753 (∼30 kb). WA-5 and pWBG753 appeared only briefly in WA, however, fusidic-acid-resistance plasmids related to pWBG753 were also present in the first European CA-MRSA at the time. Here we characterized a 72-kb conjugative plasmid pWBG731 present in multiresistant WA-5-like clones from the same period. pWBG731 was a cointegrant formed from pWBG753 and a pWBG749-family conjugative plasmid. pWBG731 carried mupirocin, trimethoprim, cadmium and penicillin-resistance genes. The stepwise evolution of pWBG731 likely occurred through the combined actions of IS257, IS257-dependent miniature inverted-repeat transposable elements (MITEs) and the BinL resolution system of the β-lactamase transposon Tn552 An evolutionary intermedi...
Source: Antimicrobial Agents and Chemotherapy - Category: Microbiology Authors: Tags: Antimicrob Agents Chemother Source Type: research