Lamellibrachia satsuma의 symbiont와 가고시마 주변 박테리아의 계통발생학적 유연관계

Abstract

Vestimentiferan tubeworms inhabit at sulfidic deep-sea hydrothermal vents and/or cold seeps environments depend on their nutrition on production of chemoautotrophic endosymbionts. It is monospecific for their host. In contrast, previous studies suggest that vestimentiferas of methane-rich seeps may host multispecific symbionts. Host specificity seemed to be maintained by vertical transmission of the bacteria through the egg to the offspring. But symbiotic process in Lamellibrachia satsuma inhabited in cold seep area of Kagoshima Bay at depths of 105~112 m is not known. Based on the 16S rRNA gene sequence analysis, bacterial clones from the surrounding sediments affiliated into 19 major lineages and dominated by clones affiliated to δ- and ε-Proteobacteria and Holophaga/Acidobacteria. To the contrary, only one symbiotic bacteria affiliated into γ-Proteobacteria was detected from Lamellibrachia satsuma. This result support the possibility that the studied cold seep tubeworm harbors a monospecific endosymbionts and which is consistent with a vertical mode of symbiont transmission. Genomic traits of endosymbionts will be investigated for the cultivation. [Supported by MEGRC]