Ito T, Hiramatsu K
Department of Bacteriology, Faculty of Medicine, Juntendo University.
Nihon Rinsho. 1997 May;55(5):1200-5.
Since the introduction of methicillin, methicillin resistant S. aureus (MRSA) was appeared in 1961 in England. MRSA produces specific penicillin-binding protein PBP2' which shows very low affinity to most of beta-lactam antibiotics. The region around mecA is called additional DNA or mec DNA and is thought to be extraspecies origin. From the study of mec DNA, it was revealed that there were three types of mec DNA. In the case of mec DNA of N315, a transposon Tn554 which encoded erythromysin and spectinomycin resistance, and a plasmid pUB110 which encoded resistance to kanamycin, tobramycin, and bleomycin were integrated. MRSA became resistant to many antibiotics during a few years which were effective at the time of introduction, such as, carbapenems, new quinolones, and minocycline. MRSA has changed their properties by obtaining resistance-genes or generating mutations on its chromosomal DNA.
自甲氧西林引入以来，耐甲氧西林金黄色葡萄球菌（MRSA）于1961年在英国出现。MRSA产生特定的青霉素结合蛋白PBP2'，它对大多数β-内酰胺类抗生素的亲和力非常低。mecA周围的区域被称为附加DNA或mec DNA，被认为是种外起源。通过对mec DNA的研究，发现有三种类型的mec DNA。以N315的mec DNA为例，整合了编码红霉素和壮观霉素抗性的转座子Tn554以及编码对卡那霉素、妥布霉素和博来霉素抗性的质粒pUB110。在几年时间里，MRSA对许多在引入时有效的抗生素产生了耐药性，如碳青霉烯类、新型喹诺酮类和米诺环素。MRSA通过获得耐药基因或在其染色体DNA上产生突变而改变了它们的特性。
