利用16S-23S rDNA间隔区快速鉴定猪链球菌和马链球菌兽疫亚种

Rapid Identification of Streptoccus suis and Streptococcus equi subs.Zooepidemicus Based on 16S-23S rDNA Intergenic Spacer Region

利用16S-23S rDNA间隔区(ISR)长度和序列的多态性,结合16S rDNA和23S rDNA的保守性,分别在16S rDNA末端和23S rDNA前端保守区设计上下游引物,进行PCR扩增。结果为21株猪链球菌均扩增出长度约为1 200 bp的片段,8株马链球菌兽疫亚种均扩出约1 300 bp的片段,其他属菌株和阴性对照无结果。因此,由PCR产物长度的不同就可快速区分猪链球菌和马链球菌兽疫亚种,这种基于ISR的PCR技术为鉴别病原微生物提供了更加简捷的方式。对2株代表菌(HA9801,ATCC 35246)的16S-23S rDNA ISR进行测序发现,猪链球菌和马链球菌兽疫亚种的ISR差异主要表现为碱基的缺失。

Swine Streptococcicosis is an important pathogen of zoonosis mainly caused by Streptoccus suis（S.su-is）orStreptococcus equi subs.zooepidemicus（S.zooepidemicus）and generates grave threat to human health andpig-breeding.We developed a new rapid molecular method of identifying S.suisand S.zby PCR using onepair of primer derived fromthe highly conserved flanking region of the 3’end of16S and the 5’end of23S rD-NA genes.The size of PCR products showed polymorphism that the lengh of 21S.suisstrains were all 1 100bp,8S.zooepidemicusstrains were 1 300 bp,and no results in other strains and negative control.The PCRmethod,based on 16S-23S rDNAintergenic spacer region（ISR） was successful in rapid identifying these twopathogen species of Swine Streptococcicosis.The sequencing results of the PCR products of the two strains,HA9801 and ATCC35246,revealed thatthe base delection in some regions of16S-23S rDNAISR induced thevariance between these two species.