Project/Area Number |
25450121
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Multi-year Fund |
Section | 一般 |
Research Field |
Applied microbiology
|
Research Institution | Japan Agency for Marine-Earth Science and Technology |
Principal Investigator |
KATO Chiaki 国立研究開発法人海洋研究開発機構, 海洋生物多様性研究分野, シニアスタッフ (90360750)
|
Co-Investigator(Renkei-kenkyūsha) |
WATANABE Nobuhisa 名古屋大学, シンクロトロン光研究センター, 教授 (70212321)
YAMADA Yasuyuki 立教大学, 理学部, 教授 (80386507)
|
Project Period (FY) |
2013-04-01 – 2017-03-31
|
Project Status |
Completed (Fiscal Year 2016)
|
Budget Amount *help |
¥4,940,000 (Direct Cost: ¥3,800,000、Indirect Cost: ¥1,140,000)
Fiscal Year 2015: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000)
Fiscal Year 2014: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
Fiscal Year 2013: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
|
Keywords | 高圧力 / 深海 / 微生物 / 酵素 / 構造解析 / 圧力 / 深海微生物 / 深海適応 / 好圧性細菌 / イソプロプルリンゴ酸脱水素酵素 |
Outline of Final Research Achievements |
3-Isopropylmalate dehydrogenase (IPMDH) from the extreme piezophile Shewanella benthica (SbIPMDH) is more pressure-tolerant than that from the atmospheric pressure-adapted Shewanella oneidensis (SoIPMDH). To understand the molecular mechanisms of this pressure tolerance, we analyzed mutated enzymes. The results indicate that only a single mutation at position 266, corresponding to Ala (SbIPMDH) and Ser (SoIPMDH), essentially affects activity under higher-pressure (HP) conditions. 3D-structural analyses of SoIPMDH suggests that penetration of three water molecules into the cleft around Ser266 under HP conditions could reduce the activity of the wild-type enzyme; however, no water molecule is observed in the Ala266 mutant. Water penetration into the cleft under HP conditions would appear to be less frequent than for the atmospheric-adapted SoIPMDH due to the reduced probability of forming a hydrogen bond, and as a consequence, SbIPMDH could adapt to the HP conditions of the deep sea.
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