根管感染中产甲烷古细菌基于mcrA序列的系统发育分析  

Phylogenetic analysis of Methanogenic archaea based on mcr A sequence data in endodontic infections

作　　者：韦艳霞[1] 郑纪伟[2] 杨锋[2] 刘佃滨[2] 

机构地区：[1]徐州医学院病原生物学与免疫学教研室,江苏徐州221004 [2]徐州医学院口腔医学院,江苏徐州221004

出　　处：《口腔生物医学》2014年第4期181-184,共4页Oral Biomedicine

基　　金：国家自然科学基金(31300029);江苏省自然科学基金(BK20130213);江苏省高校自然科学基金(12KJB320015);江苏省高校"青蓝工程"优秀青年骨干教师项目;徐州医学院优秀人才科研启动基金(D2012014)

摘　　要：目的:分析根管感染中产甲烷古细菌的多样性,建立基于功能基因--甲基辅酶M还原酶(methyl coenzyme M reductase,MCR)基因α亚基(mcr A)的系统发育树。方法:利用一对特异性引物选择性扩增感染根管中产甲烷古细菌的mcr A片段,在此基础上建立mcr A克隆文库。通过蓝白斑筛选的方法,筛选出阳性重组克隆子,进一步通过基因测序获得重组克隆子中的插入片段mcr A序列。利用Clustalx和Mega 4软件包分析mcr A序列,对其进行同源性比较和系统发育学分析。结果:4例根管样本的其中1例检出了产甲烷古细菌;构建了基于mcr A序列的系统发育树。随机选出的8个mcr A克隆片段高度同源,均为类口腔甲烷短杆菌序列型。结论:本例根管感染中产甲烷古细菌的多样性局限于类口腔甲烷短杆菌序列型。Objective：To analyze the diversity of Methanogenic archaea in endodontic infections and establish the phylogenetic tree based on functional gene mcrA.Methods：Using PCR and a pair of specific primers,mcrA was selectively amplified from total genomic DNA extracted from the microbial community in the root canal of endodontic infections.Positive clones were selected by blue-white screening,and the mcrA sequences were determined by DNA sequencing.Clustalx and Mega 4 software bags were used to analyze mcrA sequences.Phylogenetic analysis was carried out and the phylogenetic tree of methanogenic archaea was established.Results：Four root canals of endodontic infections were analyzed.We found one case positive for Methanogenic archaea.A phylogenetic tree based on functional gene mcrA was established.The mcrA fragments in endodontic infections showed high sequence similarity with Methanobrevi-bacter oralis.Conclusions：The diversity of Methanogenic archaea in the one sample from endodontic infections in this study was con-fined to Methanobrevibacter oralis-like sequence types.

关 键 词：根管感染 产甲烷古细菌 MCRA 基因 系统发育 

分 类 号：R780.2[医药卫生—口腔医学]