Japan Geoscience Union Meeting 2014

Presentation information

Oral

Symbol M (Multidisciplinary and Interdisciplinary) » M-TT Technology & Techniques

[M-TT42_2AM2] Frontiers in Geochemistry : Innovative approaches for Earth and Planetary Sciences

Fri. May 2, 2014 11:00 AM - 12:45 PM 314 (3F)

Convener:*Yusuke Yokoyama(Atmosphere and Ocean Research Institute, University of Tokyo), Hiroyuki Kagi(Geochemical Laboratory, Graduate School of Science, University of Tokyo), Shogo Tachibana(Department of Natural History Scieces, Hokkaido University), Takafumi Hirata(Graduate School of Science, Kyoto University), Urumu Tsunogai(Graduate School of Environmental Studies, Nagoya University), Katsuhiko Suzuki(Institute for Research on Earth Evolution, Japan Agency for Marine-Earth Science and Technology), Gen Shimoda(Geological Survey of Japan, AIST), Hirochika Sumino(Geochemical Research Center, Graduate School of Science, University of Tokyo), Hajime Obata(Marine inorganic chemistry division, Atmosphere and Ocean Research Institute, University of Tokyo), Yoshio Takahashi(Department of Earth and Planetary Systems Science, Graduate School of Science, Hiroshima University), Tetsuya Yokoyama(Department of Earth and Planetary Sciences, Graduate School of Science and Engineering, Tokyo Institute of Technology), Chair:Hiroyuki Kagi(Geochemical Laboratory, Graduate School of Science, University of Tokyo), Shogo Tachibana(Department of Natural History Scieces, Hokkaido University), Yusuke Yokoyama(Atmosphere and Ocean Research Institute, University of Tokyo)

12:30 PM - 12:45 PM

[MTT42-13] On the role of amino acid metabolism and a biogeochemical linkage

*Yoshinori TAKANO1, Yoshito CHIKARAISHI1, Naohiko OHKOUCHI1 (1.JAMSTEC)

Keywords:amino acid metabolism, deep-sea benthic archaea, a biogeochemical linkage

Deep-sea sediments harbor a novel and vast biosphere with yet unconstrained importance in the global biogeochemical cycle. To explore these habitats is interdisciplinary challenges for the biogeochemical and geomicrobiological scientific community. The limits of deep biosphere are on-going subject, which were not yet known in terms of environmental properties, including depth, temperature, energy availability, and geologic age; however, it is known that subseafloor microbes play a significant role in chemical reactions that were previously thought to have been abiotic. Since the novel classification by Woese and Fox (1977), Archaea, one of three domains of life, had been originally believed to exist in extreme environments including high temperature, high salinity, low oxygen concentration. However, recent advances in molecular and phylogenic approaches revealed their widespread distribution in marine and terrestrial environment including deep subsurface biosphere. The planktonic and benthic archaeal assemblages include two major phyla Euryarchaeota and Crenarchaeota. The novel phylum have been also proposed recently as Thaumarchaota, Korarchaota, and Nanoarchaeota. In the present study, we reviewed the recent knowledge of prokaryotic ecology and biogeochemistry from molecular-specific isotopic signatures. Among these, we focused on the role of amino acid metabolism and a biogeochemical linkage mediated by deep-sea benthic archaea.[ References ]Ohkouchi, N. and Takano, Y. Organic nitrogen: sources, fates, and chemistry. Treatise on Geochemistry, 10: Organic Geochemistry (Edited by Birrer, B., Falkowski, P., Freeman, K.), Vol. 12, Elsevier, pp. 251-289 (2014).Takano et al., Detection of coenzyme F430 in deep-sea sediments: A key molecule for biological methanogenesis. Organic Geochemistry, 58, 137-140 (2013).Chikaraishi et al., Determination of aquatic food-web structure based on compound-specific nitrogen isotopic composition of amino acids. Limnology and Oceanography: Method, 7, 740-750 (2010).