Carriage of an ACME II Variant May Have Contributed to Methicillin-Resistant Staphylococcus aureus Sequence Type 239-Like Strain Replacement in Liverpool Hospital, Sydney, Australia

Abstract

ABSTRACTApproximately 39% of methicillin-resistantStaphylococcus aureus(MRSA) sequence type 239 (ST239)-like bloodstream isolates from Liverpool Hospital (obtained between 1997 and 2008) carry an arginine catabolic mobile element (ACME). Whole-genome sequencing revealed that an ACME II variant is located betweenorfXand SCCmecIII, and based on pulsed-field gel electrophoresis patterns and temporal relationships of all ST239-like isolates (n= 360), ACME carriage may have contributed to subpulsotype strain replacement.