Analysis of Diversity of Mutations in the mecI Gene and mecA Promoter/Operator Region of Methicillin-Resistant Staphylococcus aureus and Staphylococcus epidermidis

Genomic diversity of mutation in the mecI gene or mecA promoter/operator region was analyzed for clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus epidermidis (MRSE). In most MRSA strains, a single base substitution was detected in either the mecI (three different positions) or the mecA promoter (two different positions), while a 28-base deletion in mecI was found in one strain. In contrast, no mutation was detected in these gene sequences of MRSE strains.