Distribution of insertion sequence-like element IS1272 and its position relative to methicillin resistance genes in clinically important staphylococci

The distribution of insertion sequence-like element IS1272 nas analyzed for clinical isolates of Staphylococcus aureus, Staphylococcus epidermidis, and Staphylococcus haemolyticus. In each of the staphylococcal species, IS1272 was detected in both methicillin-resistant (MR) and methicillin-susceptible strains of different genetic types. In MR isolates, IS1272 was generally located downstream of the truncated mecR1 gene (Delta mecR1), with an identical junction sequence occurring between Delta mecR1 and IS1272, although insertion of an additional gene sequence in the junction sequence was detected in one S. epidermidis isolate. These findings suggest that the mec element with the rearranged form of mecR1 (Delta mecR1-IS1272) has been transmitted to multiple clones of staphylococci.