通过多基因组比较的方法在5种绿球蓝细菌中识别基因组岛(英文)  

Identification of genomic islands in the genomes of five Prochlorococcus strains by multiple genomic comparison

作　　者：刘海岚[1,2] 朱军[1] 

机构地区：[1]浙江大学农业与生物技术学院生物信息研究所,浙江杭州310029 [2]四川农业大学农学院玉米研究所,四川雅安625014

出　　处：《浙江大学学报（农业与生命科学版）》2010年第5期473-484,共12页Journal of Zhejiang University:Agriculture and Life Sciences

基　　金：Project supported by the National High Technology Research and Development Program of China(No.2006AA10A102);U.S.National Science Foundation(No.DBI-0516378)

摘　　要：为探索水平基因转移在绿球蓝细菌基因组多样性中的作用,5个高光适应性绿球蓝细菌基因组被比较.先用BLASTP两两最佳匹配搜索和基因位置保守性的方法预测直系同源基因,并进一步计算每个基因组中所有基因在其他4种绿球蓝细菌基因组中直系同源基因的数量,从而达到识别外源基因的目的;而基因组岛是指由1个或几个连续外源基因组成的区域.结果表明:在5个绿球蓝细菌基因组中共识别出了16至52个不等的基因组岛,它们中的许多基因在病毒基因组或富含病毒的环境样本中都有同源基因.以上这些结果显示,在绿球蓝细菌中,病毒可能介导了基因的水平转移,从而导致了基因组的多样性.In order to explore the role of horizontal gene transfer in the divergence of genomes within the genus Prochlorococcus,the genomes of five high light-adapted strains of Prochlorococcus were compared.Firstly,both bidirectional best BLASTP search and the conservation of gene order against each other were employed to predict orthologs;then the alien genes in one Prochlorococcus strain were identified by examining how many orthologs its each gene had in the genomes of the four other strains.As for a genomic island,it refers to a region composed of one or more contiguous alien genes.The results showed that the number of genomic islands in the five genomes ranged from 16 to 52.Many of the genes in these islands showed similarity to genes found in viral genomes or sequences derived from virus-enriched environmental samples.These results suggest that viruses may have mediated horizontal gene transfer,resulting in genomic divergence amongst Prochlorococcus genomes.

关 键 词：绿球蓝细菌 基因组岛 水平基因转移 外源基因 

分 类 号：Q34[生物学—遗传学]