天津地区气单胞菌分离株的鉴定与多位点序列分型  

Characterization and multilocus sequence typing of Aeromonas strains isolated in Tianjin area

作　　者：李倩[1] 杨洪江[1] 何洋[1] 石礼涛[1] 

机构地区：[1]天津科技大学生物工程学院工业发酵微生物教育部重点实验室天津市工业微生物重点实验室,天津300457

出　　处：《微生物学通报》2013年第8期1365-1374,共10页Microbiology China

基　　金：国家自然科学基金面上项目(No.30970114)

摘　　要：【目的】研究气单胞菌菌株分类情况,并分析其致病性。【方法】采集环境样品和鱼类标本,分离并鉴定气单胞菌菌株,并运用多位点序列分型(Multilocus sequence typing,MLST)方法进行分类研究,利用PCR和测序方法分析毒力基因Aera、Hly、Aha1、GCAT和Nuc的分布。【结果】通过对分离菌株的16S rRNA基因进行分析,确认属于4种不同气单胞菌的7个分离株。发现所有菌株至少有1种毒力基因阳性,其中3株具有4种毒力基因。药物敏感实验显示,6株分离株对3种或3种以上抗菌素具有多重耐药性。最后,对看家基因gyrB、groL、gltA、metG、ppsA和recA进行分析,与MLST数据库中的等位基因序列比对,发现7株分离株均为新的不同的序列型(Sequence type,ST)。【结论】气单胞菌具有较高的遗传多样性。[Objective] To study the classification of Aeromonas genus and its pathogenicity. [Methods] Various environmental samples were collected, Aeromonas strains were isolated and characterized, and multilocus sequence typing （MLST） method was adopted to classify the isolates. [Results] Among the isolates 7 Aeromonas strains were identified, belonging to 4 dif- ferent species of the genus Aeromonas based on 16S rRNA sequence analysis. Furthermore, 5 major virulence genes including Aera, Hly, Ahal, GACT and Nuc were detected in the isolates by PCR and sequencing methods. All strains contained at least one virulence gene, and 3 of them contained 4 virulence genes, respectively. Antibiotic susceptibility test showed that 6 strains exhibited multiple drug resistances to at least 3 antibiotics. Finally, 6 housekeeping genes （gyrB, groL, gltA, metG, ppsA, and recA） were chosen for the MLST analysis by PCR and sequencing. Allele sequences were aligned by searching the MLST database. All 7 Aeromonas strains were assigned a new ST number. [Conclusion] High genetic diversity existed in Aeromonas strains.

关 键 词：气单胞菌 16S RRNA基因 耐药性 毒力基因 多位点序列分型 

分 类 号：R378[医药卫生—病原生物学]