临床分离黄杆菌金属β内酰胺酶及其基因型研究  

Detection of metallo -β- lactamase produced by clinical Chryseobacterium spp. and their genotypes

作　　者：徐元宏[1] 林祥宏[1] 朱梅[1] 夏红灯[1] 李涛[1] 王中新[1] 

机构地区：[1]安徽医科大学第一附属医院检验科安徽省细菌耐药监控中心,合肥230022

出　　处：《中华检验医学杂志》2008年第1期72-76,共5页Chinese Journal of Laboratory Medicine

基　　金：安徽省十五攻关二期科研课题资助项目（040130583）

摘　　要：目的了解临床分离黄杆菌（Chryseobacterium spp）耐药特性和金属β内酰胺酶（metallo-β-lactamase，MBL）的产酶率及其基因型。方法采用琼脂稀释法检测50株黄杆菌对18种抗生素的MIC，三纸片增效法、改良三维试验法进行MBL表型检测，PCR检测及序列分析确定MBL的基因型。接合试验检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50株黄杆菌对碳青霉烯类、氨基糖甙类及多种β内酰胺抗生素呈高度耐药，亚胺培南、美罗培南的耐药率均达82．0％，但利福平和喹诺酮类药物表现出很强的抗菌活性。表型检测33株细菌产MBL，产酶率为66．0％。MBL基因型分析结果，20株产吲哚黄杆菌携带bla IND，其中bla IND-1型9株、bla IND-2型10株、bla IND-LIKE型1株。14株脑膜炎败血黄杆菌中检出17种MBL基因，分别为blaB1 2株、blaB2 5株、blaB3 4株、blaB114株、bla GOB-1bla 1株；GOB-101株。接合试验均为阴性，质粒DNA未检出MBL基因。携带bla IND-1^-的菌株（C-5）经IEF、MBL表型检测及β内酰胺酶初筛均为阴性。结论黄杆菌具有严重的多重耐药现象，同时具有很高的MBL检出率。bla B、bla GOB和bla IND可能位于黄杆菌染色体上，不能通过细菌质粒等可移动基因元件发生不同菌株和菌株间传播。bla IND-1可能存在蛋白质的不表达或低水平表达。Objective To investigate the antibiotic resistance and the phenotype and genotype of metallo-β-lactamase in clinical isolates Chryseobacterium spp. Methods The MIC of 18 antibiotics in 50 Chryseobacterium spp. isolates 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） detection for metallo-β-lactamase gene was conducted for all isolates, and then the DNA sequence analysis was conducted for the PCR products which are positive for metallo-β-lactamase and identify genotype. 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 antibiotic resistance of 50 clinical isolates of Chryseobacterium spp. against imipenem, Meropenem was 82.0% and 82.0% respectively. However, these isolated had high resistance to gatifloxacin, levofloxacin and rifampin compared with other antibiotics. Phenotype detection showed 33 isolated produced metallo-β-lactamase using three-disc synergy test and modified three dimension test, and the incidence of producing metallo-β-lactamase was 66. 0%. Twenty isolateds producing Chryseobacterium indologenes were detected to have metallo-β-lactamase genotype by PCR amplification, among them 9 isolates containing blaIND-1 genotype and 10 isolateds containing blaIND-2 genotype. Strain CI-25 was identified to represent blaIND-LIKE genotype. Fourteen Chryseobacterium meningosepticum were detected to have metallo-β-lactamase genotype by PCR amplification, including 15 blaB and 2 blaGOB. The number of strain producing blaB1, blaB2, blaB3 and blaB11 in Chryseobacterium meningosepticum was 2, 5,4 and 4, respectively. Conjugation experiments showed that metallo-β-lactamase encoding gene cannot be transfered. The extracted plasmid of 4 strains didnot harbor metallo-β-lactamase gene. Strain C-5 was proved to have blaIND-1 gene, but its phenotype and IEF of

关 键 词：金黄杆菌属 Β内酰胺酶类 基因型 抗药性 多种 细菌 

分 类 号：R686[医药卫生—骨科学]