Characterizing a Novel Staphylococcal Cassette Chromosome mec with a Composite Structure from a Clinical Strain of Staphylococcus hominis, C34847.

Staphylococcal cassette chromosome mec (SCCmec) has predominantly been described in methicillin-resistant Staphylococcus aureus. However, studies have indicated that coagulase-negative staphylococci (CoNS) carry a larger diversity of SCC elements. We characterized a composite SCCmec element carrying an uncharacterized ccr1 and type A mec gene combination, in conjunction with a secondary element bearing ccr4, from a clinical strain of Staphylococcus hominis. The element's complex structure points to a high degree of recombination occurring in SCCmec in CoNS.