人感染猪链球菌Ⅱ型菌株的毒力基因及分子分型特征分析  

Analysis on the virulence genes and molecular typing of Streptococcus suis type 2strains isolated from patients

作　　者：朱钱迎[1] 张青 李克诚[1] 钱定良[1] 

机构地区：[1]浙江省瑞安市人民医院检验科,浙江瑞安325200

出　　处：《中国预防医学杂志》2016年第3期202-206,共5页Chinese Preventive Medicine

摘　　要：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 analyze the virulence genes and molecular typing of Streptococcus suis type 2strains isolated from patients in Rui′an of Zhejiang,and to provide the scientific evidence for the disease diagnosis,treatment and control. Methods Morphological examination,biochemical identification and multilocus sequence typing（MLST）classification of bacteria strains were conducted.Five major virulence genes including the capsular polysaccharides gene（cps2J）,the muramidate released protein gene（mrp）,the suilysin gene（sly）,the glutamate dehydrogenase gene（gdh）and extracellular factor gene（ef）were amplified by PCR.Results Three strains of Streptococcus suis type 2 were isolated from blood and cerebrospinal fluid samples.MLST analysis identified 2sequence types of ST1（1strain）and ST7（2strains）.Two virulence gene types of ef＋/cps2J-/mrp-/sly＋/gdh＋（1strain）and ef＋/cps2J-/mrp＋/sly＋/gdh＋（2strains）were identified. Conclusions It′s the first time that S.suis strains are isolated in Rui′an area.ST1 is highly pathogenic and ST7 is found to be consistent with epidemic strains in Sichuan,which might originate from Sichuan.Analysis of virulence genes shows that all three strains are highly pathogenic type.

关 键 词：猪链球菌Ⅱ型 病原学检查 毒力基因 多位点序列分型技术(MLST) 

分 类 号：R446.5[医药卫生—诊断学]