[Molecular genetics of MRSA].
Methicillin resistance in staphylococci is explained by any of the several alterations of penicillin-binding proteins. In most (97%) of the cases, however, it is caused by acquisition of mecA gene. The mecA gene seems to be laterally transmissible among various staphylococcal species, although the frequency of transmission may not be high in view of the observed rather homogeneous nature of genetic backgrounds of the MRSA strains which were isolated all over the world. Evolution of MRSA to acquire higher level of resistance to beta-lactam antibiotics has been noticed in recent years. Such phenotypic evolution is explained by a genetic alteration involving the mec regulator genes, mecR1 and mecI, of the prototype MRSA strain.
Hiramatsu
K
K
Department of Bacteriology, Juntendo University.
D000818:Animals; D005798:Genes, Bacterial; D006801:Humans; D016106:Methicillin Resistance / Q000235:genetics*; D013211:Staphylococcus aureus / Q000145:classification / Q000235:genetics* / Q000378:metabolism