猪链球菌长沙分离株的鉴定与16S rRNA系统进化分析

摘要

The aim of this study was to identify 2 strains of Streptococcus suis isolated in Changsha City and elucidate their phylogenetic relationship through the 16S rRNA . The 16S rRNA of 2 strains was amplified by polymerase chain reaction (PCR) through universal primer of 16S rRNA . The products of 16S rRNA of 2 strains were obtained successfully with length about 1 500 bp. The products were sequenced successfully then the sequences were submitted to GenBank . And the sequences were compared with related sequence through online BLAST in NCBI , showing the 2 strains of Streptococcus suis were Streptococcus suis type 2 . The identification result through the 16S rRNA was consistent with traditional method . Then the phylogenetic tree of 16S rRNA was constructed through the Mege 4.0 software. The phylogenetic tree showed that the 2 strains of Streptococcus suis were at the same evolutionary branch with most of Streptococcus suis type 2 and had the nearest phylogenetic relationship with Streptococcus suis 05ZYH33 in Sichuan Province . In conclusion , Streptococcus suis could be quickly and accurately identified through the 16S rRNA and this method could be applied in rapid detection . The 2 strains of Streptococcus suis isolated in Changsha City were Streptococcus suis type 2 and was not variable in 16S rRNA gene.%目的 对2株猪链球菌(Streptococcus suis,SS)长沙分离株进行分离培养和分子鉴定,并对其16S rRNA基因进行测序,阐明其系统进化关系.方法 利用分离培养法对2株 SS进行分离鉴定,同时对分离株16S rRNA 基因进行PCR扩增和核苷酸序列测定,将测序结果提交GenBank,通过在线Blast同源性分析进行菌株鉴定,并与传统培养鉴定方法进行比较,利用Mega4.0软件构建SS长沙分离株系统进化树.结果 成功扩增出2株菌的目的 片段,通过测序后Blast同源性分析,证实2株菌株均为SS,且与传统鉴定方法结果一致,进化树显示长沙2株SS和国内外2型位于同一进化分支上,同四川的05ZYH33参考株亲缘关系最近.结论 通过16S rRNA基因可以准确快速鉴定SS,可应用于应急检测,长沙2株猪链球菌属于SS2型,与其他SS2分离株16S rRNA 基因同源性高,未发生变异.