致病性钩端螺旋体的多位点序列分型研究

目的 通过对致病性钩端螺旋体(简称钩体)多位点序列分型(MLST)分析,了解国内与全球致病性钩体种群结构及其分子进化.方法 应用16SrRNA基因测序和MLST分析方法对不同来源、不同时期国内钩体分离菌株与国际参考菌株进行分析,并与国内7株疫苗株结果平行比较,同时收集已公开的来自不同国家和不同时期1 238株致病性钩体...

Multilocus sequence typing of pathogenic Leptospira

Multilocus sequence typing (MLST) was conducted to analyze pathogenic Leptospira to understand the population structure and molecular evolution of pathogenic Leptospira in China and worldwide. We used 16S rRNA gene sequencing and MLST analysis to detect domestic Leptospira isolates and international reference strains from different sources and periods, and compared the results with those from seven domestic vaccine strains in parallel. Furthermore, the gene species and published MLST data on 1 238 pathogenic Leptospira strains from different countries and periods were collected to analyze the population structure. The 16S rRNA gene sequencing analysis indicated that the main gene species of the seven international reference strains and 47 domestic Leptospira strains were Leptospira interrogans, which accounted for 71.4% and 59.6%, respectively. The seven international reference strains revealed seven different ST types, and the 47 domestic Leptospira strains included 15 ST types and 24 previously unreported ST types. MLST cluster analysis indicated that L. interrogans, L. borgpeterseni and L. weilii strains formed separate branches. Seven Chinese vaccine strains with different ST types were also located in different sub-branches within the L. interrogans species. The phylogenetic tree revealed that the 1 238 Leptospira strains isolated from different countries in the past 100 years included 16 predominated evolutionary clusters, which mainly comprised ST17, ST34, ST149, ST1 and ST37. A total of 236 Leptospira strains from China were divided into four main evolutionary clusters, and the main epidemic genotypes were ST1, ST128, ST17 and ST143. The gene species and ST types of epidemic strains differed among countries. Pathogenic Leptospira strains were widely cross-infected in different host species and spread among countries. We obtained data on pathogenic Leptospira gene species and MLST gene polymorphisms in China to systematically understand the population structure and genetic evolution relationship of pathogenic Leptospira in China and worldwide. Our findings may provide scientific guidance for the follow-up monitoring and tracing of pathogenic Leptospira.