Cultivation of uncultured microorganisms involved in anaerobic crude oil biodegradation

Research Project

Project/Area Number	17H04970
Research Category	Grant-in-Aid for Young Scientists (A)
Allocation Type	Single-year Grants
Research Field	Biofunction/Bioprocess
Research Institution	National Institute of Advanced Industrial Science and Technology
Principal Investigator	Mochimaru Hanako 国立研究開発法人産業技術総合研究所, 地質調査総合センター, 主任研究員 (90462861)
Project Period (FY)	2017-04-01 – 2020-03-31
Project Status	Completed (Fiscal Year 2019)
Budget Amount *help	¥24,180,000 (Direct Cost: ¥18,600,000、Indirect Cost: ¥5,580,000) Fiscal Year 2019: ¥5,850,000 (Direct Cost: ¥4,500,000、Indirect Cost: ¥1,350,000) Fiscal Year 2018: ¥5,850,000 (Direct Cost: ¥4,500,000、Indirect Cost: ¥1,350,000) Fiscal Year 2017: ¥12,480,000 (Direct Cost: ¥9,600,000、Indirect Cost: ¥2,880,000)
Keywords	原油分解 / メタン生成 / メタン生成菌 / 培養 / 油田 / ガス田 / 嫌気的 / 古細菌 / 細菌 / メタン / 原油 / 微生物 / メタン生成古細菌
Outline of Final Research Achievements	The development of technology to convert crude oil currently remaining in depleted oil fields into methane is necessary to ensure we efficiently use our natural resources. The purpose of this study is to elucidate the mechanism of biogenic crude oil degradation and methane formation that is thought to occur in deep underground oil reservoir environments. In this study, cultures grown in high-pressure and atmospheric-pressure conditions simulating the reservoir environment, were carried out to obtain a crude oil-degrading, methane producing microbial culture. We obtained a methanogenic culture using fatty acids that are likely intermediate metabolites of the crude oil degradation process. Furthermore, we succeeded in obtaining both enrichment cultures and pure cultures of uncultured bacteria. The cultivation of these novel microorganisms and the elucidation of the substrates they utilize have contributed to the understanding of the mechanism by which methanogenesis occurs.
Academic Significance and Societal Importance of the Research Achievements	原油の回収率は一般に20-60%であり、枯渇油田とされてもその半量ほどは地下に残されている。本研究では、この原油をメタンに変換し、天然ガスとして回収する技術の開発を目指している。原油分解メタン生成がどのような微生物によりどのような反応経路で起こっているのか、そのメカニズムを明らかにすることで、その反応を利用し促進させることが可能となるはずである。本研究ではその反応を担う、未培養で機能が未知であった微生物の役割を解明した。