High-pressure-induced water penetration into 3-isopropylmalate dehydrogenase
High-pressure-induced water penetration into 3-isopropylmalate dehydrogenase
复制标题
高压诱导水渗透至 3-异丙基苹果酸脱氢酶
DOI：
10.1107/s1744309112001443
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发表时间：
2012
期刊：
影响因子：
--
通讯作者：
N.
中科院分区：
文献类型：
--
作者：
Nagae;T.;Kawamura;T.;Chavas;LMG.;Niwa;K.;Hasegawa;M.;Kato;C. and Watanabe;N.
生活在马里亚纳海沟等深海的生物必须适应极高的压力环境。例如，在极端条件下，纯性嗜压菌希瓦氏菌DB21MT-2 （SbIPMDH）的3-异丙基苹果酸脱氢酶保持活性，而陆地细菌S. oneidensis MR-1 （SoIPMDH）的脱氢酶失去活性。为了揭示这两种IPMDHs之间的差异，以~ 1.5 Å分辨率确定了它们的结构。两种酶的结构比较表明，在常压下，SbIPMDH比SoIPMDH具有更开放的形态和更大的内腔体积。这种松散的SbIPMDH结构可以帮助它避免压力引起的固有结构扭曲，并在比SoIPMDH更高的压力下保持活性。
Organisms living in deep seas such as the Mariana Trench must be adapted to the extremely high pressure environment. For example, the 3-isopropylmalate dehydrogenase from the obligate piezophile Shewanella benthica DB21MT-2 (SbIPMDH) remains active in extreme conditions under which that from the land bacterium S. oneidensis MR-1 (SoIPMDH) becomes inactivated. In order to unravel the differences between these two IPMDHs, their structures were determined at ∼1.5 Å resolution. Comparison of the structures of the two enzymes shows that SbIPMDH is in a more open form and has a larger internal cavity volume than SoIPMDH at atmospheric pressure. This loosely packed structure of SbIPMDH could help it to avoid pressure-induced distortion of the native structure and to remain active at higher pressures than SoIPMDH.