著者
吉崎 もと子 渋谷 岳造 鈴木 勝彦 清水 健二 中村 謙太郎 大森 聡一 高井 研 丸山 茂徳
出版者
一般社団法人日本地球化学会
雑誌
日本地球化学会年会要旨集 2011年度日本地球化学会第58回年会講演要旨集
巻号頁・発行日
pp.58, 2011 (Released:2011-09-01)

様々な分野の研究から、初期地球の熱水系にはメタン生成菌のような水素をエネルギー源とする化学合成独立栄養細菌を一次生産者に持つ生態系が繁栄しており、水素は生命誕生・進化の重要な鍵であったと考えられる。本研究では、初期地球熱水系では当時の表層にあったとされるAl枯渇型コマチアイトが水素発生を担っていたと考え、熱水実験を通して初期地球のコマチアイト熱水系における水素発生量とその反応過程を検証した。その結果、コマチアイトの熱水変質による顕著な水素発生量を確認した。また、実験生成物の分析を行った結果、かんらん石では従来提唱されてきたように蛇紋石化反応に伴う磁鉄鉱生成によって水素が発生しているのに対し、コマチアイトでは別の水素発生プロセスが進行し、それは、粘土鉱物への?V価鉄の分配によるH2Oの還元であると推定した。コマチアイトの熱水変質による水素発生量は、現生のかんらん岩熱水系で観測される水素濃度に匹敵し、現世のかんらん岩熱水系と同様に、初期地球熱水系の生態系に豊富な量の水素を供給していたことが示唆される。
著者
高井 研
出版者
日本高圧力学会
雑誌
高圧力の科学と技術 (ISSN:0917639X)
巻号頁・発行日
vol.20, no.4, pp.362-376, 2010 (Released:2010-12-11)
参考文献数
58

To date, together with rapidly developed culture-independent molecular techniques, knowledge in biomass, phylogenetic diversity and biogeography of microbial components has been extensively characterized in various terrestrial and oceanic habitats of deep biosphere. However, the general sketch of phenotypic and physiological diversity of subsurface microorganisms has remained poorly understood as most of the indigenous subsurface microbial components still escape from the laboratory cultivations. In this article, the physiological properties of the microorganisms that have been cultivated from various subsurface environments are overviewed.

14 0 0 0 OA M&E編集長から

著者
高井 研
出版者
日本微生物生態学会
雑誌
日本微生物生態学会誌 (ISSN:24241989)
巻号頁・発行日
vol.37, no.1, pp.44-45, 2022-03-01 (Released:2022-03-12)
著者
高井 研
出版者
一般社団法人 日本高圧力技術協会
雑誌
圧力技術 (ISSN:03870154)
巻号頁・発行日
vol.57, no.3, pp.137-147, 2019 (Released:2019-06-26)
参考文献数
39

It is more than 60 years since certain microbial populations were first discovered in deep-sea environments such as abyssal and hadal zones (>4000m) of ocean. According to the development of deep-sea technology and various sampling tools, the microbiological explorations have renewed our view of deep-sea microbial ecosystems: it was previously considered to be the static habitats and communities composed of minor extremophilic and long-surviving populations successively from the surface and overlying ocean environments while it is being recognized as the dynamic habitats and communities composed of genetically diverse and functionally active populations responding to variable oceanographic, geological and geochemical events and impacts. The most outstanding examples are discoveries of dark energy ecosystems in the deep-sea and subseafloor environments, represented by various types of chemosynthetic microbial communities completely independent of photosynthetic production in the deep-sea hydrothermal systems, an enormous biomass and diversity of deep subseafloor microbial communities beneath the global oceanfloor, and unique hadal biosphere at great depths of >6000m in ultradeep trenches. The findings have revolutionized our understanding of limits of life and biosphere and the origin and early evolution of life in the Earth. Even very recently, the previously unknown microbial ecosystem has been being found in the deep-sea and subseafloor environments. I can be proud that Japanese deep-sea exploration techniques and microbiologists have greatly contributed to these findings. In this article, the brief history and recent advance are reviewed.
著者
加藤 千明 高井 研
出版者
日本宇宙生物科学会
雑誌
Biological Sciences in Space (ISSN:09149201)
巻号頁・発行日
vol.14, no.4, pp.341-352, 2000 (Released:2006-02-01)
参考文献数
44
被引用文献数
5 7

Knowledge of our Planet's biosphere has increased tremendously during the last 10 to 20 years. In the field of Microbiology in particular, scientists have discovered novel “extremophiles”, microorganisms capable of living in extreme environments such as highly acidic or alkaline conditions, at high salt concentration, with no oxygen, extreme temperatures (as low as -20°C and as high as 300°C), at high concentrations of heavy metals and in high pressure environments such as the deep-sea. It is apparent that microorganisms can exist in any extreme environment of the Earth, yet already scientists have started to look for life on other planets; the so-called “Exobiology” project. But as yet we have little knowledge of the deep-sea and subsurface biosphere of our own planet. We believe that we should elucidate the Biodiversity of Earth more thoroughly before exploring life on other planets, and these attempts would provide deeper insight into clarifying the existence of extraterrestrial life. We focused on two deep-sea extremophiles in this article; one is “Piezophiles”, and another is “Hyperthermophiles”. Piezophiles are typical microorganisms adapted to high-pressure and cold temperature environments, and located in deep-sea bottom. Otherwise, hyperthermophiles are living in high temperature environment, and located at around the hydrothermal vent systems in deep-sea. They are not typical deep-sea microorganisms, but they can grow well at high-pressure condition, just like piezophiles. Deming and Baross mentioned that most of the hyperthermophilic archaea isolated from deep-sea hydrothermal vents are able to grow under conditions of high temperature and pressure, and in most cases their optimal pressure for growth was greater than the environmental pressure they were isolated from. It is possible that originally their native environment may have been deeper than the sea floor and that there had to be a deeper biosphere. This implication suggests that the deep-sea hydrothermal vents are the windows to a deep subsurface biosphere. A vast array of chemoautotrophic deep-sea animal communities have been found to exist in cold seep environments, and most of these animals are common with those found in hydrothermal vent environments. Thus, it is possible to consider that the cold seeps are also one of slit windows to a deep subsurface biosphere. We conclude that the deep-sea extremophiles are very closely related into the unseen majority in subsurface biosphere, and the subsurface biosphere probably concerns to consider the “exobiology”.
著者
高井 研 中村 龍平 山本 正浩
出版者
独立行政法人海洋研究開発機構
雑誌
基盤研究(A)
巻号頁・発行日
2012-05-31

研究期間において、(1)現場深海熱水噴出孔において硫化物チムニーの内外で600mV程度の起電力が潜在的に存在し、実際の電子伝達能を有していること、(2)にもかかわらず、実験室内実験において、チムニーに生息する微生物群集を植種源として、天然チムニー電極や様々な電極を支持体とした電気合成微生物群集の増殖が観察されないこと、が明らかになった。これらの結果を踏まえて、深海熱水現場環境での電気合成微生物群集の増殖実験を行い、電気合成微生物群集の形成を示唆する結果を得た。自然深海熱水噴出孔のチムニーにおいて電気合成微生物群集が生育可能であることが明らかになった。