J Korean Soc Microbiol.
2000 Jun;35(3):215-224.
Clonal analysis of methicillin-resistant Staphylococcus aureus strains in
Korea
- Affiliations
-
- 1Department of Microbiology, College of Medicine, Dankook
University, San 29, Anseo-dong, Cheonan, Choongnam, 330-714, South Korea.
minkim@anseo.dankook.ac.kr
Abstract
-
In this study, the distribution of the mec regulator genes and
the presence of the mutation in mecI gene and mec promoter region among
50 MRSA clinical isolates derived from a single university hospital in
Korea were analyzed. Among 50 MRSA strains, 13 strains had a deletion of
mecI gene, and 37 strains were found to have mutations in mecI gene or
mecA promoter region corresponding to a presumptive operator of mecA,
i.e., the binding site of the repressor protein. Furthermore, in order to
track the evolution of methicillin-resistant Staphylococcus aureus (MRSA)
distributed in Korea, we determined the MRSA clonotype by combined use of
genetic organization patterns of mec regulator genes, ribotype, and
coagulase type. As the result, 48 of 50 MRSA strains could be classified
into four distinct clones. Clonotype I is characterized by the coagulase
type 3, deletion of mecI gene, and ribotype 1 shared by NCTC10442, the
first reported MRSA isolate in England (9 strains). Clonotype II is
characterized by the coagulase type 4, C to T substitution at position
202 of mecI gene, and ribotypes 2, 3 and 4 shared by 85/3619 strain
isolated in Austria (10 strains). Clonotype III is characterized by the
coagulase type 2, mutations of mecA promoter region and/or mecI, and
ribotypes 4, 5, and 6 shared by N315 strain isolated in Japan (25
strains). Clonotype IV is characterized by the coagulase type 4, deletion
of mecI gene, and ribotype 7 (4 strains). The clonality of two strains
could not be determined due to their undefined ribotype.