CAJ | 학술논문

目的明确万古霉素耐药肠球菌(VRE)耐药转座子结构及分子分型.方法收集2006年4月至2007年4月杭州市5家医院21株VRE菌株,用Etest法进行抗菌药物的药敏试验,并通过PCR、接合试验、质粒提取、耐药转座子结构、脉冲凝胶电泳(PFGE)、多位点序列分型(MIST)及多位点串联重复序列分型(MLVA)进行研究.结果 21株VRE基因型及表型均符合vanA.属于10个不同的PFGE型,7个不同的MLST分型,4个不同的MLVA分型,其中18株属于克隆复合体CC17,另外3株为ST343与CC17接近.所有VRE菌株均对利奈唑胺及替加环素敏感.多对引物对转座子的不同区域的PCR扩增并进行序列拼接、比对,发现其中2株VRE菌株携带典型的耐药转座子Tn1546,其余19株VRE菌株均携带一种新的与Tn1546相似耐药转座子,均在vanXY之间反向插入IS1485.18株VRE菌株均可通过滤膜接合试验进行万古霉素耐药转移,接合菌均含有约54 000 bp大小的质粒.结论杭州市5家医院21株VRE菌株均为vanA表型及基因型,发现了一种新的万古霉素耐药转座子结构.21株VRE菌株经MLST分型属于7个不同的序列分型,属于或接近易在医院环境里生存并在近年来迅速造成了全球播散的克隆复合体CC17.
목적 명학만고매소내약장구균(VRE)내약전좌자결구급분자분형.방법 수집2006년4월지2007년4월항주시5가의원21주VRE균주,용Etest법진행항균약물적약민시험,병통과PCR、접합시험、질립제취、내약전좌자결구、맥충응효전영(PFGE)、다위점서렬분형(MIST)급다위점천련중복서렬분형(MLVA)진행연구.결과 21주VRE기인형급표형균부합vanA.속우10개불동적PFGE형,7개불동적MLST분형,4개불동적MLVA분형,기중18주속우극륭복합체CC17,령외3주위ST343여CC17접근.소유VRE균주균대리내서알급체가배소민감.다대인물대전좌자적불동구역적PCR확증병진행서렬병접、비대,발현기중2주VRE균주휴대전형적내약전좌자Tn1546,기여19주VRE균주균휴대일충신적여Tn1546상사내약전좌자,균재vanXY지간반향삽입IS1485.18주VRE균주균가통과려막접합시험진행만고매소내약전이,접합균균함유약54 000 bp대소적질립.결론 항주시5가의원21주VRE균주균위vanA표형급기인형,발현료일충신적만고매소내약전좌자결구.21주VRE균주경MLST분형속우7개불동적서렬분형,속우혹접근역재의원배경리생존병재근년래신속조성료전구파산적극륭복합체CC17.
Objective To determine the structures of resistance transposons and muhilocus sequencing typing(MLST)in the vancomycin resistant enterococcus(VRE).Methods Twenty-one VRE strains were isolated from five hospitals in Hangzhou.The resistance to antimicrobial agents was determined by Etest.Polymerase chain reaction(PCR),conjugation,plasmid extract,transposon structures,pulse field gel electrophoresis(PFGE),muhilocus sequencing typing(MLST),and multiple-locus variable-number tandem repeat analysis(MLVA)were carried out.Results All of the 21 VRE strains harbored the vanA gene.These strains were divided into 10 PFGE types,7 sequence types(STs)and 5 MLVA types.All of these VRE strains were susceptible to linezolid and tigecycline.The vanA genes in two VRE strains were located in transposon Tnl546,and those in the other 19 VRE strains were located in transpeson Tnl546- like,with ISl485 inserted in vanXY.Vancomycin resistance of 1 8 VRE isolates was transferred by filter mating. All of these conjugants had a plasmid containing a molecular size of about 54 000 bo.Conclusions These 21 VRE strains were all caused by the vanA gene and divided into 7 MIST types.A novel trasnposon was detected.Most of these VRE isolates belonged to the clonal complex(CC17)by MIST,which was the hospital-adapted and pandemic VRE clonal complex.