2013 Fiscal Year Final Research Report

Phylogeny, function and physiology of microbes playing important roles in carbon flow in the marine subsurface environments

Research Project

Project/Area Number	24770033
Research Category	Grant-in-Aid for Young Scientists (B)
Allocation Type	Multi-year Fund
Research Field	Ecology/Environment
Research Institution	Japan Agency for Marine-Earth Science and Technology
Principal Investigator	HOSHINO Tatsuhiko 独立行政法人海洋研究開発機構, 高知コア研究所, 研究員 (30386619)
Project Period (FY)	2012-04-01 – 2014-03-31
Keywords	地下生命圏 / 炭素フラックス / 一酸化炭素 / 機能遺伝子 / 微生物生態
Research Abstract	In the past decades, microbial community in the marine subsurface environments have been studied, and total biomass of microbial cells in the marine subsurface was estimated to contribute to 0.6% of the total living biomass carbon on the Earth. However, roles of those deep life were still largely unknown. In this study, we first investigated diversity of cooS gene, which encodes beta subunit of anaerobic carbon monoxide dehydrogenase, in the subseafloor environments. DNA was extracted from marine sediments obtained at Gulf of Mexico, Fuan de Fuca, South Pacific Gyre, Nankai Trough, and off Shimokita peninsula by IODP expeditions. Fragment of cooS gene was amplified by PCR and sequenced. The sequencing results indicated that diversity of cooS gene in the sediments were very small comparing to 16S rRNA gene. Almost all obtained sequences were not related to the known cooS gene sequences in the database and formed distinct clusters in a phylogenetic tree.