中国不可分群脑膜炎奈瑟菌的分子分型分析

目的了解我国血清不可分群(non-serogroupable,NG)脑膜炎奈瑟菌分子分型特征。方法选取我国2005-2011年分离的104株血清不可分群脑膜炎奈瑟菌作为研究对象,采用多位点序列分型(MLST)和聚合酶链反应(PCR)基因分群(A、B、C、W、E、X、Y、Z、H、I、L、K、cnl)方法,检测其ST序列群及基因群。结果 104株不可分群脑膜炎奈瑟菌中,基因群分布为荚膜基因缺失菌株(capsule null locus,cnl)(36株)、B群(20株)、C群(14株)、W群(9株)、E群(9株)、X群(3株)和Y群(3株),余下10株未鉴定出基因群;未发现其他基因群菌株。MLST分型将104株NG菌株分为45种ST型,其中14种为新的ST型;17种ST型可归为7个序列群(65株);cnl菌株全属于ST-198序列群,B群和C群菌株以ST-4821为优势序列群,W群以ST-11和ST-174序列群为主。结论我国NG脑膜炎奈瑟菌具有基因多态性,其中ST-198序列群全部为cnl菌株。

Molecular typing of non sero-groupable Neisseria meningitidis in China

Objective To understand the molecular typing characteristics of 104 non sero-groupable（ NG） Neisseria meningitidis strains in China. Methods A total of 104 NG N. meningitidis strains isolated in 2005- 2011 were characterized by multilocus sequence typing（MLST）. Genogroups（A,B,C,W,E,X,Y,Z,H,I,L,K and cnl）were determined by PCR. ResultsThe 104 NGN. meningitidisstrains included capsule null locus（cnl） strains（n = 36）,genogroup B strains（ n = 20）,genogroup C strains（ n = 14）,genogroup W strains（ n = 9）,genogroup E strains（n =9）,genogroup X strains（n = 3） and genogroup Y strains（n = 3）. There were 10 strains which could not be genogrouped. No NG isolates belonging to other genogroups were identified. By MLST analysis, 104 NG N. meningitidis were identified to belong to 45 sequence types（ ST） clonal complex,14 of which were new sequence types; 17 sequence types can be grouped into 7 ST clonal complex（n = 65）; cnlstrains all belonged to ST-198 complex.The predominant ST complex of genogroup B and genogroup C was ST-4821,and ST-11,ST-174 were predominant in ST complex of genogroup W strains. Conclusion The NG N. meningitidis strains in China showed significant gene polymorphism,and the ST-198 complex strains were all identified as cnl strains.