产吲哚金黄杆菌金属β-内酰胺酶及其基因型检测  

Detection of Metallo-β-lactamase Produced by Chryseobacterium indologenes and Their Genotypes

作　　者：林祥宏[1] 李涛[1] 朱梅[1] 凌华志[1] 陈晓莉[1] 徐元宏[1] 

机构地区：[1]安徽医科大学第一附属医院检验科,安徽合肥230022

出　　处：《中华医院感染学杂志》2008年第1期17-21,共5页Chinese Journal of Nosocomiology

基　　金：安徽省十五攻关二期科研课题(040130583)

摘　　要：目的了解产吲哚金黄杆菌(Chryseobacteriumindologenes)耐药特性和金属β-内酰胺酶(MBL)的产酶率及其基因型。方法琼脂稀释法检测25株产吲哚金黄杆菌的最低抑菌浓度(MIC),增效法、改良三维试验法进行MBL表型检测,聚合酶链反应(PCR)筛查MBL和整合酶基因,全编码基因检测以及序列分析以确定IND型MBL的基因型;接合试验监测耐药基因是否具有可转移性,等电聚焦电泳(IEF)测定β-内酰胺酶等电点(pI)。结果产吲哚金黄杆菌对亚胺培南、美罗培南的耐药率为88.0%,但利福平、加替沙星、左氧氟沙星的耐药率均<12.0%;表型检测19株细菌产MBL,PCR初筛检测仅IND-like通用引物扩增出20株阳性,全编码基因分析,blaIND-1型9株,blaIND-2型10株,IND-like型MBL基因1株,其中5株blaIND碱基序列和演绎的氨基酸序列均发生改变;接合试验均为阴性,19株检测到1(17株)或2个(2株)pI值,携带blaIND-1的菌株(CI-5)经IEF和MBL表型检测均为阴性。结论产吲哚金黄杆菌具有很高的MBL检出率,本地区的产吲哚金黄杆菌以产IND-1、IND-2型MBL为主,blaIND可能存在蛋白质的不表达或低水平表达。OBJECTIVE To investigate the antibiotical resistance and to understand the phenotype and genotype of metallo-β-lactamase in Chryseobacterium indologenes. METHODS The MIC to 25 C. indologenes strains was detected by agar dilution method. Phenotype of metallo-β-lactamase was detected by three-disc synergy test and modified three dimension test. Polymerase chain reaction （PCR）amplification for both metallo-β-lactamase and integrase gene was conducted for all isolates. Complete coding gene of metallo-β-lactamase and their DNA sequence analysis was conducted. Conjugation experiment was used to study the transmission of metallo-β-lactamase encoding gene. pIs Of β-lactamase was measured by isoelectric focusing assay. RESULTS The antibiotical resistance of C. indologenes to imipenem and meropenem was 88. 0%, respectively. However, gatifloxacin, levofloxacin and rifampin had better antimicrobiotial ability to C. indologenes compared with other antibiotics in MIC Nineteen strains were identified to produce metallo-β-lactamase using three-disc synergy test and modified three dimension test. Twenty strains were detected to have metallo-β-lactamase genotype by PCR amplification using IND-like common prime sets and roar prime sets of complete coding gene. Among them, 9 strains were detected to have blaIND-1 genotype and 10 strains to have blaIND-2 genotype, strain CI-25 was identified to have blaIND-like genotype. The mutation of base sequences and amino acid sequences in 5 strains were found simultaneously. Conjugation experiment showed that metallo-β-lactamase encoding gene couldn＇t transfer. Nineteen strains had 1 or 2 bands on isoelectric focusing electrophoresis. Strain CI-5 was proved to have blaIND-1, but phenotype of metallo-β-lactamase was negative. CONCLUSIONS C. indologenes has high rate of metallo-^- lactamase producing, and thus it is difficult to treat. The major genotype of metallo-β-lactamase for C. indologenes is blaIND-1 and blaIND-2 in Hefei. The expression of blaIND could exist negative

关 键 词：产吲哚金黄杆菌 多药耐药 金属Β-内酰胺酶 基因型 

分 类 号：R378[医药卫生—病原生物学]