东太平洋多金属结核区两个站位深海沉积物细菌多样性

Bacterial diversity in deep-sea sediments from two stations in the east Pacific polymetallic nodule province

【目的】为了解东太平洋中国多金属结核勘探合同区西区2个站位(WBC1305和WBC1316A)深海沉积物细菌群多样性。【方法】直接提取环境样品总基因组,通过PCR和TA克隆策略构建了2个站位6个层次16S r RNA基因文库,对2个站位沉积物表层泥样中细菌多样性和群落结构特征进行分析,并通过构建系统发育树,进行系统发育学分析。【结果】2个站位6个文库共获得有效克隆533个,其中472个克隆包括α-变形菌纲、β-变形菌纲、γ-变形菌纲、δ-变形菌纲、浮霉菌门、酸杆菌门、硝化螺旋菌门、放线菌门、绿弯菌门、厚壁菌门、拟杆菌门、迷踪菌门、芽单胞菌门、Hydrogenedentes、Chlorobi和Nitrospinae16个细菌类群,而另外61个克隆为不可分类细菌类群。【结论】结果表明γ-变形菌纲和厚壁菌门分别是WBC1305和WBC1316A站位的优势种群;WBC1316A站位细菌群落结构更加丰富和复杂。

[Objective] The objective of this study was to assess bacterial diversity in sediment samples from two stations （WBC 1305 and WBC 1316A） in the Pacific polymetallic nodule province. [Methods] The environmental total DNAs were extracted, and 6 bacterial 16S rRNA gene libraries were generated from 6 sediment layers. The Shannon diversity index and Simpson dominance index were calculated for each bacterial community and then compared. The bacterial community structure of each sediment sample was analyzed, and the results were used to construct phylogenetic trees. [Results] In total, 533 bacterial clones were obtained from 6 bacterial clone libraries. Among these 533 clones, 472 clones could be assigned to 16 phylogenetic groups （Acidobacteria, Actinobacteria, Alpha, Beta, Delta, gamma-Proteobacteria, Bacteroidetes, Chloroflexi, Firmicutes, Gemmatimonadetes, Nitrospirae, Planctomycetes, Elusimicrobia, Hydrogenedentes, Chlorobi, and Nitrospinae）, whereas the remaining 61 clones could not be classified into any known groups. [Conclusion] The bacterial communities in sediments from WBC 1305 are dominated mainly by gamma-Proteobacteria and from WBC 1316A by Firmicutes. In addition, the bacterial community structure at WBC 1316A is more abundant and complex than that at WBC 1305.