广东首株W135群流行性脑脊髓膜炎奈瑟菌的分子特征分析

目的 分析广东首次从患者脑脊液分离到的W135群流行性脑脊髓膜炎奈瑟菌(Neisseria meningitidis,N. meningitidis) 的分子特征.方法 复苏培养并用奈瑟菌生化鉴定系统(API NH)生化鉴定从患者脑脊液分离到的1株W135群N.meningitidis,以本地近年分离的1株C群和3株A群N. meningitidis 为对照;通过DNA序列测定分析外膜蛋白编码基因(porA、porB)可变区型别;通过多位点序列分型(multilocus sequence typing,MIST),采用Splits Tree在线软件分析进化关系,研究其分子特征.结果 该W135群N.meningitidis的porA可变区(va)型别为P1.5,2,属主要致病型别之一;porB的可变区Ⅰ、Ⅳ、Ⅴ、Ⅶ分别为1、1、1、17型,无可变区Ⅵ、Ⅷ;MIST等位基因谱为:2、123…4 38、4、6,序列型(ST)为2960,属ST-11/ET-37 克隆系.4株对照菌株porA的VR型别均为P1.20,porB可变区Ⅳ为7型,无可变区Ⅶ;C群对照株属ST-4821克隆系,3株A群属ST-5克隆系.结论 该W135群N.meningitidis的分子特征与国外分离株相同,而与本地流行的A群及C群菌株不同.

Molecular characters of epidemic cerebrospinal W135 Neisseria meningitidis strain firstly isolated in Guangdong province

Objective To analyze the molecular characters of the W135 Neisseria meningitidis strain fimfly isolated from patients in Guangdong province.Methods Biochemical profile by using the API NH system (bio-Merieux,Fmnce)was used for confirmation,and sere-grouping of the meningococeal isolates including one serogroup W135,one serogroup C and three serogroups of a Neisseria meningitidis isolated from patients in Guangdong province in recent two years were performed.The subtype was determined after amplifying porA and porB respectively from the genome DNA of Neisseria meningitidis.Multilocus sequence typing (MIST) was performed for determining the allele profiles and the sequence types(sTs).The polygenetic tree was obtained by analyzing the allele profiles with program Splits tree online.The molecular characters of the serogroup W135 Neisseria meningitidis was analyzed by its evolution relationship and the variable regions in porA and porB which encoding the outer membranes proteins (OMPs).Results The subtype determined by porA variable regions of the serogroup W135 Neisseria meningitidis was P1.5,2,which was one of the most invasive types.The types of variable regions (VRs)Ⅰ,Ⅳ,Ⅴ,Ⅶ with porB were 1,1,1,17,and there was no Ⅵ and Ⅷ inporB.The allele profile of the W135 strain in this study was 2,123,4,3,8,4,6,and its sequence type was ST-2960,which belonged to ST-11/ET-37 clone complex.The subtypes of the serogroup C and serogroup A strains were P1.20,while their types of VR Ⅳ were all 7,and they all hadn't VR Ⅶ in porB.The strain serogroup C belonged to ST-4821 clone complex,and the 3 serogroup A strains belonged to ST-5 clone complex.Condusion The molecular character of the serogroup W135 Neisseria meningitidis should be the sanle with the strains isolated in foreign country,and be different from the epidemic types in the area.This serogroup W135 Neisseria meningitis isolated from patients in Guangdong for the first time was thought to be a new type appearing in the local area.