九孔鲍(Haliotis diversicolor supertexta)育苗期养殖水体细菌的群落结构

Community structure of bacteria in abalone farm pond water during seed breeding of Haliotis diversicolor supertesta

为研究九孔鲍(Haliotis diversicolor supertexta)育苗期养殖水体细菌的群落结构,用细菌通用引物构建了细菌16S rRNA基因克隆文库.从文库中随机挑选31个克隆子进行限制性片段长度多态性(RFLP)分析,得到20个不同的RFLP带型.对代表性克隆子进行测序,序列分析和系统进化分析结果表明鲍苗养殖池水体中细菌遗传多样性非常丰富.主要分为3大类群:γ-变形菌纲、α-变形菌纲和黄杆菌纲细菌,分别占58%、32%和10%.γ-变形菌纲细菌中以弧菌最多,包括已知的鲍病原弧菌,其次是海洋螺菌目细菌.α-变形菌纲细菌主要与GenBank库中未培养的克隆子序列最相似,其中红细菌科细菌最丰富,占所分析克隆子数目的26%.本研究结果表明九孔鲍育苗期养殖水体中存在大量未培养的、未知菌属的细菌.

To examine the community structure of bacteria in abalone farm pond water during seed breeding of Haliotis diversicolor supertesta, the 16S rRNA gene clone library was constructed using primers universal for the domain bacteria. In total, 31 clones ran- domly selected were screened by PCR-restriction fragment length polymorphism （PCR-RFLP） analysis, and 20 clones with unique RFLP pattern were sequenced. The results revealed a high bacterial genetic diversity in abalone farm pond water, and all the cloned sequences were clustered into 3 major lineages： γ-Proterbacteria, α-Proterbacteria and Flavobaeteria, accounting for 58% , 32% and 10%, respectively. Vibrio spp. were the most abundant members within the γ-Proterbacteria, they included some known pathogens of abalones. Species of order Oceanospirillales were the second abundant members. Theα-Proterbacteria were mainly related to uncultured bacteria in GenBank database, and most of them （ about 26% ） belonged to the family Rhodobacteraceae. The results presented here indicated that there existed a great number of uncultured and unknown bacteria in the abalone farm pond water.