摘要
为研究甲氧西林耐药金黄色葡萄球菌（ＭＲＳＡ）对氨基糖苷类抗生素的耐药机制，应用氨基糖苷抗生素耐药谱推测法、核素标记分析法、Ｓｏｕｔｈｅｒｎ印迹试验和斑点杂交试验对１００株ＭＲＳＡ进行了耐药谱研究。结果：根据细菌对氨基糖苷抗生素的耐药谱，１００株ＭＲＳＡ可以分成４类，６５株细菌产生ＡＡＣ（６′）ＡＰＨ（２″）钝化酶，２４株产生ＡＡＣ（６′）ＡＰＨ（２″）＋ＡＰＨ（３′），１０株产生ＡＡＣ（６′），还有１株产生ＡＡＣ（６′）ＡＰＨ（２″）＋ＡＮＴ（４′）；根据对５０株ＭＲＳＡ的核素标记分析和斑点杂交试验获得的结果与其耐药谱推测的结果是一致的；Ｓｏｕｔｈｅｒｎ试验显示编码ＡＡＣ（６′）钝化酶的基因位于染色体上。提示：ＭＲＳＡ对氨基糖苷抗生素耐药的主要机制是由于该菌产生氨基糖苷钝化酶。
To study the resistance mechanism of methicillin resistant staphylococcus aureus(MRSA) to aminoglycosides, the modifying enzyme extrapolated assay from aminoglycoside resistance profiles, radio labelled assay, as well as Southern blot and dot blot tests were applied. Results showed that the aminoglycoside resistance profiles of 100 strains of MRSA could be divided into following four groups. Group I included 65 strains of MRSA producing 6′ acetyltransferase 2″ phosphotransferase [AAC(6′) APH(2″)];Groups Ⅱ included 24 strains producing AAC(6′) APH(2″)+APH(3′);Group Ⅲ included 10 strains producing AAC(6′) and group Ⅳ included one strain producing AAC(6′) APH(2″)+ANT(4′). The results of radio labelled assay and dot blot test showed the modifying enzyme patterns of aminoglycoside produced by 50 strains of MRSA were the same as which extrapolated form the resistant profiles. Results of southern blot test showed that the homologue sequence of AAC(6′) had strong reaction of hybridization in chromosomal DNA of 50 MRSA strains. This result suggested that gene encoding AAC(6′) modifying enzyme is located on chromosomal DNA. It can be concluded that the main resistance mechanism of MRSA to aminoglycosides is due to the production of aminoglycoside modifying enzymes(AMEs).
出处
《中华传染病杂志》
CAS
CSCD
北大核心
1997年第3期125-129,共5页
Chinese Journal of Infectious Diseases
基金
国家自然科学基金
关键词
甲氧西林
抗药性
金黄色葡萄球菌
Methicillin resistance Staphylococcus aureus Antibiotics,aminoglycoside Aminoglycoside-modifying enzyme
