产ESBLs肠杆菌科细菌对氨基糖苷类抗生素耐药机制研究.docx

中国抗生素杂志2005年9月第30卷第9期·555·文章编号：1001—8689(2005)09—0555—04产ESBLs肠杆菌科细菌对氨基糖苷类抗生素耐药机制研究段建眷吕晓菊。赵燕冯萍俞汝佳宗志勇高燕渝熊亚莉(四川大学华西医院感染性疾病中心，四川大学生物治疗国家重点实验室，成都610041)摘要：目的研究产超广谱p内酰胺酶(extendedspectrumbeta—lactamases，ESBLs)肠杆菌科细菌对氨基糖苷类抗生素的耐药分子机制。方法采用PCR方法对耐氨基糖苷类抗生素的产ESBLs菌株进行氨基糖苷类耐药机制研究，并同时对钝化酶基因DNA测序，进行网上基因相似性检索。结果20株耐氨基糖苷类的产ESBLs肠杆菌科细菌中存在氨基糖苷钝化酶基因，分别有aac(3)一I、aac(3)一II、aac(6’)一I、aac(6’)一II、ant(2”)一I和aph(37)一VI，以aac(3)一I、aac(3)一II和aac(6’)一l为主。部分菌株同时可含有多种钝化酶基因。DNA测序分析结果与国外报道已知相应氨基糖苷钝化酶DNA测序结果一致。结论产ESBLs肠杆菌科细菌中普遍存在氨基糖苷钝化酶，四川I大学华西医院分离得到的氨基糖苷类耐药的产ESBLs肠杆菌科细菌的钝化酶基因型主要是aac(6’)一I、aac(3)一II、aac(3)一I和ant(2”)一I。关键词：肠杆菌科细茵；超广谱p内酰胺酶；氨基糖苷类钝化酶；PCR；序列测定中图分类号：R378．2文献标识码：AAminoglycosidesresistancemechanismsofextendedspectrump—lactamases—producingEnterobacteriaceaeDuanJian—chun，LuXiao—ju，ZhaoYan，FengPing，ZongZhi—yong，YuRu—jia，GaoYan—yuandXiongYa—li(DepartmentofInfectiousDiseases，WestChinaHospitalofSichuanUniversity，Chengdu610041)ABSTRACTObjectiveToinvestigatethemolecularmechanismsoftheaminoglycoside—resistanceinESBLs—producingEnterobacteriaceaestrains．MethodsThenucleotidesequenceofaminoglycoside—modify—ingenzymegenesinESBLs-·producingplusaminoglycoside—-resistantstrainsamplifiedbyPCRweredetectedbyautomaticsequencer，andcomparedwithrelativeDNAsequencingreportedbyothersinInternetGenBankthroughBlastxsearching．ResultsAmong20aminoglycoside—resistantplusESBI，S—producingstrains，aminoglycoside—modifyingenzymegeneshavebeenfound．Theywereaminoglycosideacetyltransferase(3)-Igeneaac(3)一I]，aminoglycosideacetyltransferase(3)一IIgeneaac(3)一II]，aminoglycosideacetyltransferase(67)-Igeneaac(67)一I]，aminoglycosideacetyltransferase(67)一IIgeneaac(6’)一II]，aminoglycosideadenyl—transferase(2”)-Igene[ant(2”)一I]andaminoglycosidephosphoryltransferase(3’)一VIgene[aph(37)-VII．TheDNAsequencesofaminoglycoside—modifyingmodifyingenzymesgeneswereinconcordancewithotheraminoglycoside—modifyingenzymegenesreferedinInternetGenBank．ConclusionsAminoglycoside—modify—ingenzymewerecommonlyexiste．dinESBLs—producingstrainsofEnterobacteriaceae．Thegenes