不同血清群致病性钩端螺旋体PFGE分析研究

目的 了解不同血清群致病性钩体的脉冲场凝胶电泳(pulsed-field gel electrophoresis,PFGE)带型特征。方法 应用PFGE方法对65株不同血清群致病性钩体国际、国内参考菌株和疫苗株进行分型,并以此聚类分析,同时与菌株的多位点序列分型(multilocus sequence typing,MLST)、多位点串联重复序列数变化分析(multilocus VNTR analysis, MLVA)分型结果进行比较研究。结果 不同血清群致病性钩体基因组DNA经NotⅠ酶切电泳后,获得了较高清晰度酶切图谱,各条带分离良好。65株钩体菌株分为61种PFGE型别。相同的血清群的钩体菌株的PFGE型别不尽相同。比较分析结果显示尽管PFGE、MLST和MLVA之间的分型结果不尽相同,但都具有较高的分辨率。聚类分析显示这些菌株可形成11个大小不一进化簇,呈现多点分散进化特征。结论 获得致病性钩体分子分型的第一手资料,为后续钩体分子溯源及流行病学研究提供科学指导。

PFGE analysis of leptospirosis in different serum groups

To understand the zone characteristics of pulsed-field gel electrophoresis (PFGE) of pathogenic leptospires in different serum groups, the PFGE method was used to classify 65 international and domestic reference strains and vaccine strains of pathogenic leptospires with different serogroups. Cluster analysis was carried out with multilocus sequence typing (MLST) and multilocus VNTR analysis (MLVA). Using Not I enzyme digestion electrophoresis, a high definition enzyme digestion map of pathogenic Leptospira genomic DNA of different serum groups was obtained; 65 strains of Leptospira were divided into 61 PFGE types. The PFGE types of Leptospira strains in the same serum group were different. The results of comparative analysis showed that, although the typing results of PFGE, MLST and MLVA were different, they all indicated a high rate of differentiation. Cluster analysis demonstrated that these strains could form 11 evolutionary clusters of different sizes, showing the characteristics of multi-point dispersion evolution. The primary data of molecular typing of pathogenic leptospires can provide scientific guidance for molecular tracing and epidemiological study.