Evidence for chemoautotrophic symbiosis in a Mediterranean cold seep clam (Bivalvia: Lucinidae):: comparative sequence analysis of bacterial 16S rRNA, APS reductase and RubisCO genes
Evidence for chemoautotrophic symbiosis in a Mediterranean cold seep clam (Bivalvia: Lucinidae):: comparative sequence analysis of bacterial 16S rRNA, APS reductase and RubisCO genes
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DOI：
10.1111/j.1574-6941.2006.00194.x
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发表时间：
2007-01-01
影响因子：
4.2
通讯作者：
Sibuet, Myriam
中科院分区：
文献类型：
--
作者：
Duperron, Sebastien;Fiala-Medioni, Aline;Sibuet, Myriam
对光泽蛤（双壳类：光泽蛤科）和自养硫化物氧化细菌之间的共生关系的研究主要集中在浅水沿海物种，关于深海物种的信息很少。在这里，我们研究的共生的蛤，类似Lucinoma kazani，这是最近收集的沉积物核心从新的冷泉网站附近的尼罗河深海扇，地中海东部，深度范围从507至1691米。通过16 S rRNA基因序列分析，在鳃组织中发现了一种与硫氧化共生体相关的优势细菌型。第二种与螺旋体序列相关的螺旋体类型在94个克隆的文库中鉴定了两次。编码APS还原酶α亚基和核酮糖-1，5-二磷酸羧化酶加氧酶的基因序列的比较分析支持优势共生体可以进行硫化物氧化和自养的假设。鳃的透射电子显微镜照片证实了硫化物氧化细菌的优势，显示典型的空泡，和三角洲C-13值测量鳃和足组织进一步支持的假设为一个化能自养来源的主机碳营养。
Symbioses between lucinid clams (Bivalvia: Lucinidae) and autotrophic sulphide-oxidizing bacteria have mainly been studied in shallow coastal species, and information regarding deep-sea species is scarce. Here we study the symbiosis of a clam, resembling Lucinoma kazani, which was recently collected in sediment cores from new cold-seep sites in the vicinity of the Nile deep-sea fan, eastern Mediterranean, at depths ranging from 507 to 1691 m. A dominant bacterial phylotype, related to the sulphide-oxidizing symbiont of Lucinoma aequizonata, was identified in gill tissue by comparative 16S rRNA gene sequence analysis. A second phylotype, related to spirochete sequences, was identified twice in a library of 94 clones. Comparative analyses of gene sequences encoding the APS reductase alpha subunit and ribulose-1,5-bisphosphate carboxylase oxygenase support the hypothesis that the dominant symbiont can perform sulphide oxidation and autotrophy. Transmission electron micrographs of gills confirmed the dominance of sulphide-oxidizing bacteria, which display typical vacuoles, and delta C-13 values measured in gill and foot tissue further support the hypothesis for a chemoautotrophic-sourced host carbon nutrition.