13:45 〜 14:00
[MIS14-07] 化学特性の異なる蛇紋岩化反応サイトにおける比較ゲノム微生物学的解析
★招待講演
キーワード：蛇紋岩化反応、初期地球、エンセラダス、ゲノム微生物
Serpentinization is a process whereby water interacts with reduced mantle rock called peridotite to produce a new suite of minerals (e.g., serpentine), a highly alkaline fluid, and hydrogen. The hydrogen and carbon dioxide present in the system are thought to react under the highly reducing and alkaline conditions, leading to the formation of methane and hydrocarbons and the concomitant production of carbon monoxide, formate, formaldehyde and methanol. Given that the reduced compounds delivered from the water-rock reaction can support microbial energy metabolisms, such serpentinization systems have been viewed as potential habitats for early life or the other planetary bodies.
Studies of serpentinizing environments to date have shown that these ecosystems host extremely low-abundance microbial communities, which is presumably attributed to the multiple extremes: 1) the highly-alkaline condition of the fluid; 2) the extremely low concentrations of oxidants (electron acceptors); and, 3) the low levels of and nutrients (available carbon and phosphate). Although it is known that the serpentinization reaction results in unique geochemical conditions overall, terrestrial ophiolite The Cedars (USA), Voltri Massif (Italy), Santa Elena Ophiolite (Costa Rica), terrestrial intrusive body Cabeço de Vide (Portugal), shallow-water hydrothermal deposit Prony Bay (New Caledonia), deep-sea Mariana serpentine have different geochemical properties due to the reacting waters (natural and seawater) and the depths. Here, we present the microbial genomes from serpentinizing springs in different sites and discuss how diverse chemical characteristics define the microbial communities and metabolisms in this system.
Studies of serpentinizing environments to date have shown that these ecosystems host extremely low-abundance microbial communities, which is presumably attributed to the multiple extremes: 1) the highly-alkaline condition of the fluid; 2) the extremely low concentrations of oxidants (electron acceptors); and, 3) the low levels of and nutrients (available carbon and phosphate). Although it is known that the serpentinization reaction results in unique geochemical conditions overall, terrestrial ophiolite The Cedars (USA), Voltri Massif (Italy), Santa Elena Ophiolite (Costa Rica), terrestrial intrusive body Cabeço de Vide (Portugal), shallow-water hydrothermal deposit Prony Bay (New Caledonia), deep-sea Mariana serpentine have different geochemical properties due to the reacting waters (natural and seawater) and the depths. Here, we present the microbial genomes from serpentinizing springs in different sites and discuss how diverse chemical characteristics define the microbial communities and metabolisms in this system.