双歧杆菌Ⅱ型毒素-抗毒素系统-MazEF的分子进化分析  

The Molecular Evolution of Type Ⅱ Toxin-antitoxin(TA) System-MazEF in Bifidobacterial Genomes

作　　者：韦艳霞[1] 刘佃滨[2] 郑纪伟[2] 尤红娟[1] 张鹏[1] 李阳[1] 汤仁仙[1] 

机构地区：[1]徐州医学院基础医学院,江苏徐州221004 [2]徐州医学院口腔医学院

出　　处：《中国医学创新》2014年第34期16-19,共4页Medical Innovation of China

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项目(12KJB320015)

摘　　要：目的:对双歧杆菌属编码的Ⅱ类毒素-抗毒素(TA)系统MazEF进行分子进化分析。方法:利用PSI-BLAST在NCBI中搜索获得双歧杆菌编码的MazF分子序列,在NCBI蛋白数据库、核酸数据库分别下载其他菌属基因组编码的MazF蛋白序列和本研究所涉及菌属的16 S rRNA序列,应用Clustal X2和MEGA4软件对Maz F做分子进化分析。结果:共搜索到双歧杆菌株染色体编码毒素蛋白MazF 26个。分子进化分析显示:整个双歧杆菌属的MazF保守性不好;MazF与16 S rRNA的共进化仅在个别菌种中发现,大部分MazF的聚类结果与相应菌种16 S rRNA的聚类结果不同。结论:双歧杆菌中的TA系统MazEF可能是通过基因的水平转移整合入基因组中,属于菌株非核心基因组部分。Objective： To perform molecular evolution analysis of MazEF in genomes of Bifidobacterium.Method：The Protein sequences of MazF in bifidobacterial genomes were obtained by employing the PSI-BLAST search from NCBI. The Protein sequences of MazF encoded by other bacteria were obtained from non-redundant protein database of NCBI. All of the 16 S rRNA sequences used in this study were obtained from non-redundant nucleotide database of NCBI. Clustal 字2 and MEGA4 were used to analyze molecular evolution of Maz F. Result：The total number of MazF in bifidobacterial genomes were searched of 26 The molecular evolution analysis showed that MazF in bifidobacterial genomes had less conservation;the co-evolution of MazF with the 16 S RNA was only observed in individual species and most homologous analysis results of MazF were not in concordance with 16 S rRNA. Conclusion： MazEF was integrated in bifidobacterial chromosomes through horizontal transfer, which was a part of the non-core genome.

关 键 词：MazEF 毒素-抗毒素系统 分子进化 双歧杆菌 

分 类 号：R378[医药卫生—病原生物学]