VOLUME CHANGES ON PROTEIN-FOLDING
VOLUME CHANGES ON PROTEIN-FOLDING
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DOI：
10.1016/s0969-2126(00)00065-4
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发表时间：
1994-07-15
期刊：
影响因子：
5.7
通讯作者：
CHOTHIA, C
中科院分区：
文献类型：
--
作者：
HARPAZ, Y;GERSTEIN, M;CHOTHIA, C
背景：蛋白质在低压下折叠时体积变化很小，但在高压下，未折叠状态更紧凑。到目前为止，这种行为的分子起源还没有得到解释：它是相反的预期从模型的疏水效应的基础上转移的非极性溶质从水到有机solvent.Results：我们重新确定的平均体积所占据的残留物在内部的蛋白质。新的残留物体积小于先前基于更有限数据的计算所给出的残留物体积。它们表明蛋白质内部的堆积密度非常高。残基在蛋白质中占据的体积与它们在溶液中占据的体积的比较表明，脂肪族基团在蛋白质内部的体积比在溶液中的体积小，而肽和带电基团的体积较大。取消这些体积变化的原因是，折叠的净变化是非常小的。结论：这里所示的蛋白质内部的密度异常高意味着，包装力发挥更重要的作用，蛋白质的稳定性比迄今为止被认为。
Background: Protein volumes change very little on folding at low pressure, but at high pressure the un folded state is more compact. So far, the molecular origins of this behaviour have not been explained: it is the opposite of that expected from the model of the hydrophobic effect based on the transfer of non-polar solutes from water to organic solvent.Results: We redetermined the mean volumes occupied by residues in the interior of proteins. The new residue volumes are smaller than those given by previous calculations which were based on much more limited data. They show that the packing density in protein interiors is exceptionally high. Comparison of the volumes that residues occupy in proteins with those they occupy in solution shows that aliphatic groups have smaller volumes in protein interiors than in solution, while peptide and charged groups have larger volumes. The cancellation of these volume changes is the reason that the net change on folding is very small.Conclusions: The exceptionally high density of the protein interior shown here implies that packing forces play a more important role in protein stability than has been believed hitherto.