铜绿假单胞菌parC基因突变与耐氟喹诺酮的关系  

Topoimerase Ⅳ parC Mutation in Quinolone-Resistant Clinical Isolatesof Pesudomonas aeruginosa

作　　者：谭艳[1] 方治平[1] 宋晓红[1] 张海军[2] 沈月华[2] 

机构地区：[1]四川大学华西医学中心药理教研室,四川成都610041 [2]四川省公安厅法医检验科,四川成都610041

出　　处：《微生物学杂志》2003年第6期35-37,56,共4页Journal of Microbiology

摘　　要：研究了成都地区临床分离的铜绿假单胞菌拓扑异构酶ⅣparC基因突变与耐氟喹诺酮类药物的关系。测定临床分离的55株铜绿假单胞菌的MIC值,从中筛选出1株敏感菌和8株耐药菌,以标准敏感菌株ATCC27853作为质控菌株。用PCR反应扩增parC基因的喹诺酮耐药决定区(QRDR),扩增产物片段长度为396bp,同时对上述10株菌的PCR产物进行测序分析。临床分离敏感菌和标准菌株ATCC27853的parC基因序列与国外报道的序列相同,而R25,R42,R43,R44等4株耐药菌株在87位(TCGCG→TTG)均有突变,该单位点突变引起氨基酸由Ser→Leu的改变,此外,新发现在所有耐药菌株115位有一静止突变(GCT→GCG),该突变未引起氨基酸的改变。拓扑异构酶ⅣparC基因突变是铜绿假单胞菌对氟喹诺酮类药物产生耐药性的机制之一,以87位的突变最为常见。To study parC mutation of clinical Pesudomonas aeruginosa strains. By determing the MIC values,one sensitive strain and eight resistant strains were select from 55 clinical P. aeruginosa strains.Taking standard sensitive strain-ATCC27853 as control,the quinolone-determining region (QRDR) of the parC gene were amplified by PCR and directly sequenced the PCR products(396bp) by PCR-DNA. In this study the quinolone-sensitive strain and standard sensitive strain-ATCC27853 had the same sequence as reported. By DNA-sequencing R25,R42,R43 and R44 resistant strains were found having an TCG-to-TTG mutation in codon 87,leading to the amino acid substitution of a Serine for a Leucine.In addition,a new silent mutation(GCT-to-GCG) were found in codon 115,which did not lead to amino acid change.The mutations of parC gene is one of mechanisms which response for resistance to fluroquinolone in Pesudomonas aeruginosa ,the Ser-87-Gly mutations was the most frequent.

关 键 词：铜绿假单胞菌 PARC基因 耐氟喹诺酮药物 基因突变 

分 类 号：R978.1[医药卫生—药品] Q933[医药卫生—药学]