论文部分内容阅读
目的掌握浙江瑞安地区人感染猪链球菌Ⅱ型菌株毒力因子及分子分型情况,为诊断、治疗和制定防控措施提供科学依据。方法对2012年瑞安地区分离的病原菌进行形态学观察、生化鉴定及多位点序列分型(MLST)分析,并选取胞外因子(ef)、荚膜多糖(cps2J)、溶菌酶释放蛋白(mrp)、溶血素(sly)、谷氨酸脱氢酶(gdh)等5个猪链球菌Ⅱ型主要毒力基因进行PCR检测。结果在血、脑脊液样本中分别分离出3株猪链球菌,均属于Ⅱ型,MLST分型结果显示:1株属于ST1型、2株属于ST7型。3株病原菌分为2种毒力基因型,其中ef+/cps2J-/mrp-/sly+/gdh+1株,ef+/cps2J-/mrp+/sly+/gdh+2株。结论在瑞安地区首次分离到人感染猪链球菌Ⅱ型,其中ST1克隆株属于全球常见高致病株,ST7克隆株与四川流行株相一致,可能来源于四川。毒力基因型分析表明,这3株病原菌均为高致病型。
Objective To understand the virulence factors and molecular typing of Streptococcus suis serotype Ⅱ strains in Ruian area of Zhejiang province and to provide a scientific basis for diagnosis, treatment and prevention and control measures. Methods Morphological observation, biochemical identification and multi-site sequence typing (MLST) analysis of the pathogens isolated in 2012 in Ruian area were carried out. The effects of extracellular factor (ef), capsular polysaccharide (cps2J), lysozyme releasing protein ), Hemolysin (sly), glutamate dehydrogenase (gdh) five Streptococcus suis type Ⅱ major virulence genes PCR detection. Results Three strains of Streptococcus suis were isolated from blood and cerebrospinal fluid respectively. All of them belonged to type Ⅱ. The result of MLST typing showed that one strain belonged to ST1 type and two belonged to ST7 type. Three strains of pathogens were divided into two virulence genotypes, of which ef + / cps2J- / mrp- / sly + / gdh + 1 and ef + / cps2J- / mrp + / sly + / gdh + 2 strains. Conclusions The human isolate of Streptococcus suis type Ⅱ was isolated from the swine for the first time. Among them, the ST1 clone belongs to the most common pathogenicity strain in the world. The ST7 clone is consistent with the endemic strain in Sichuan, probably from Sichuan Province. Virulence genotype analysis showed that all three pathogens were highly pathogenic.