海洋蛭弧菌DA5全基因组测序及序列分析

为深入挖掘和利用海洋蛭弧菌及其基因资源, 本研究利用Illumina HiSeq测序平台对一株属于嗜盐噬菌弧菌(Halobacteriovorax)的海洋蛭弧菌DA5进行了全基因组测序, 对基因组进行组装、基因预测和功能注释, 并与其他8株蛭弧菌进行了比较基因组分析。结果显示: DA5基因组大小为3.27Mb, GC含量为36.5%, 预测编码基因3175个。在DA5基因组中注释到303个基因具有直系同源蛋白簇分类, 与代谢通路相关基因1239个。比较基因组分析表明: DA5符合海洋蛭弧菌基因组的基本特征, 与其他8株蛭弧菌共有467个同源基因家族, 而DA5特有基因为266个。DA5中与细胞运动相关基因62个, 其中编码甲基受体趋化蛋白、鞭毛蛋白、鞭毛马达及其开关蛋白基因均与嗜盐噬菌弧菌BAL6_X的对应基因亲缘关系最近。对DA5全基因组序列的注释和功能分析, 为深入研究其捕食特性和作用机制, 并更有效地利用其防控海水养殖细菌病害提供了基础。

Whole-genome sequencing and analysis of marine Bdellovibrio-and-like organism DA5

To explore and utilize marine Bdellovibrio-and-like organisms (BALO) and their genes, the whole genome of Halobacteriovorax sp. DA5 was sequenced using the Illumina HiSeq platform. Then, fragment assembly, gene prediction and functional annotation were analyzed in comparison with those of other eight BALO strains. The results showed that the genome size of strain DA5 is 3.27 Mb with GC content of 36.5%, and encodes 3175 predicted genes, including 303 genes found in the Clusters of Orthologous Groups (COG) database and 1239 genes related to metabolic pathways. Comparative genomic analysis showed that DA5 has typical characteristics identified in genomes of the marine BALOs, and there were 467 homologous gene families common in genomes of DA5 and other eight BALOs, while 266 unique genes were found only in DA5 genome. Among all the 62 genes associated with cell motility of strain DA5, members such as methyl-accepting chemotaxis protein, putative flagellin, flagellar motor proteins, and flagellar motor switch proteins were most affiliated phylogenetically with those of Halobacteriovorax sp. BAL6_X. Therefore, annotation and functional analysis of the genome sequence of DA5 provide insight into its predatory property and interaction mechanism with host, and establish the basis for DA5 as biocontrol agent against harmful bacteria occurring in marine aquaculture.