Pore loops of the AAA+ ClpX machine grip substrates to drive translocation and unfolding.
Pore loops of the AAA+ ClpX machine grip substrates to drive translocation and unfolding.
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DOI：
10.1038/nsmb.1503
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发表时间：
2008-11
影响因子：
16.8
通讯作者：
Sauer, Robert T.
中科院分区：
文献类型：
--
作者：
Martin, Andreas;Baker, Tania A.;Sauer, Robert T.
蛋白水解AAA+解折叠酶使用ATP水解来驱动构象变化，所述构象变化使蛋白质底物机械变性，然后将多肽通过窄孔移位到降解室中。我们表明，酪氨酸在孔环的六聚体ClpX解折叠酶连接ATP水解机械工作，在展开和易位过程中抓住基板。在甚至几个ClpX亚基中的芳环的去除导致滑移，使底物变性的频繁失败，以及底物展开的能量成本的巨大增加。酪氨酸是一个保守的芳香族-疏水基序的一部分，在这两个残基的突变的影响随驻留亚基的核苷酸状态而变化，支持一个模型，其中这些孔环中的核苷酸依赖性构象变化驱动底物易位和展开，芳香环将力传递到多肽底物。
Proteolytic AAA+ unfoldases use ATP hydrolysis to power conformational changes that mechanically denature protein substrates and then translocate the polypeptide through a narrow pore into a degradation chamber. We show that a tyrosine in a pore loop of the hexameric ClpX unfoldase links ATP hydrolysis to mechanical work by gripping substrates during unfolding and translocation. Removal of the aromatic ring in even a few ClpX subunits results in slippage, frequent failure to denature substrate, and an enormous increase in the energetic cost of substrate unfolding. The tyrosine is part of a conserved aromatic-hydrophobic motif, and the effects of mutations in both residues vary with the nucleotide state of the resident subunit, supporting a model in which nucleotide-dependent conformational changes in these pore loops drive substrate translocation and unfolding, with the aromatic ring transmitting force to the polypeptide substrate.
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影响因子：
16
作者：
Martin, Andreas;Baker, Tania A.;Sauer, Robert T.
通讯作者：
Sauer, Robert T.
影响因子：
64.5
作者：
Singleton, MR;Sawaya, MR;Wigley, DB
通讯作者：
Wigley, DB
DOI：
10.1073/pnas.0600031103
发表时间：
2006-02-28
影响因子：
11.1
作者：
Bieniossek, C;Schalch, T;Baumann, U
通讯作者：
Baumann, U
影响因子：
4.8
作者：
Lum, R;Tkach, JM;Glover, JR
通讯作者：
Glover, JR
影响因子：
4.8
作者：
Park, EY;Rho, YM;Chung, CH
通讯作者：
Chung, CH