南海冷泉区贻贝(Bathymodiolus platifrons)附生菌的分离培养与多样性分析

Isolation and phylogenetic analysis of epiphytic bacteria from mussels collected from the cold seep

以采集后适应培养0~24 h以及添加甲烷和硫化钠培养24~240 h的南海冷泉区深海贻贝(Bathymodiolus platifrons)为材料,取其鳃部,分析附生菌的多样性与适应性变化状况。共分离鉴定出贻贝附生菌270株,对菌株的16S r DNA进行聚类分析,结果表明所分离菌株主要分布在4个门,21个属,其中变形菌的数量最多且多样性高。分析发现原位新采集的贻贝鳃部附生菌的多样性较高,6 h后附生菌的多样性明显降低。分别添加甲烷和硫化钠对深海贻贝进行培养,甲烷组与碳代谢有关的假单胞菌的数量逐渐增多,且在甲烷组240 h中发现2株食烷菌属菌株。硫化钠组的芽孢杆菌属所占比例升高。此外还发现4株潜在的新种。本研究实现了深海冷泉区贻贝的实验室培养,并对贻贝鳃部附生菌群结构进行了分析,丰富了海洋极端环境微生物资源库,并为深入解析贻贝与其附生菌之间的相互作用关系奠定了基础。

Epiphytic bacteria play an important role in substance absorption and metabolism of mussels.Gills of mussels in different experimental groups were collected at different times,and the epiphytic bacteria were cultured and separated.A total of270strains were obtained.Four strains,which might be new species,were discovered.The diversity of epiphytic bacteria decreased sharply in6h sterile-seawater cultivation.In the methane treatment group,the number of Pseudomonas increased gradually.In the group treated with Na2S,Bacillus associated with sulfur circulation increased gradually.It is important to study the interaction between mussels and epiphytic bacteria and to explore the biological resources in extreme deep sea environments.