Protein GB1 folding and assembly from structural elements.
Protein GB1 folding and assembly from structural elements.
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蛋白质 GB1 从结构元件折叠和组装。
DOI：
10.3390/ijms10041552
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发表时间：
2009-04-08
影响因子：
5.6
通讯作者：
Linse S
中科院分区：
文献类型：
--
作者：
Bauer MC;Xue WF;Linse S
随着盐浓度的增加，蛋白质GB1结构域（PGB1）的折叠从固有非结构化子结构域的合作组装转变为部分预折叠结构的组装。预折叠的盐依赖性导致了在生理盐条件下观察到的最小稳定性。我们的结论是基于用圆二色光谱研究了两个PGB1片段在盐浓度和温度下的重构。盐可以诱导c端片段（残基41 - 56）的β-发夹结构增加，而对分离的n端片段（残基1 - 41）的结构没有明显的影响。随着越来越多的证据表明片段互补与相应完整蛋白稳定性之间的相互关系，我们还发现盐对重构的影响可以通过完整蛋白稳定性的盐依赖性来预测。我们的数据显示，我们的变体（具有突变T2Q， N8D, N37D，并以类似野生型的方式重组）在生理盐浓度周围表现出最低的平衡关联常数，在低盐浓度和高盐浓度下都观察到更高的亲和力。这证实了盐对完整蛋白变性稳定性的影响，与低盐和高盐浓度相比，生理盐的稳定性较低。因此，我们得出结论，重组报告了控制蛋白质天然状态的分子因素。
Folding of the Protein G B1 domain (PGB1) shifts with increasing salt concentration from a cooperative assembly of inherently unstructured subdomains to an assembly of partly pre-folded structures. The salt-dependence of pre-folding contributes to the stability minimum observed at physiological salt conditions. Our conclusions are based on a study in which the reconstitution of PGB1 from two fragments was studied as a function of salt concentrations and temperature using circular dichroism spectroscopy. Salt was found to induce an increase in β-hairpin structure for the C-terminal fragment (residues 41 – 56), whereas no major salt effect on structure was observed for the isolated N-terminal fragment (residues 1 – 41). In line with the increasing evidence on the interrelation between fragment complementation and stability of the corresponding intact protein, we also find that salt effects on reconstitution can be predicted from salt dependence of the stability of the intact protein. Our data show that our variant (which has the mutations T2Q, N8D, N37D and reconstitutes in a manner similar to the wild type) displays the lowest equilibrium association constant around physiological salt concentration, with higher affinity observed both at lower and higher salt concentration. This corroborates the salt effects on the stability towards denaturation of the intact protein, for which the stability at physiological salt is lower compared to both lower and higher salt concentrations. Hence we conclude that reconstitution reports on molecular factors that govern the native states of proteins.
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影响因子：
2.9
作者：
Berggård, T;Julenius, K;Linse, S
通讯作者：
Linse, S
影响因子：
64.8
作者：
Munoz, V;Thompson, PA;Eaton, WA
通讯作者：
Eaton, WA
影响因子：
3.4
作者：
Lindman, S;Xue, WF;Linse, S
通讯作者：
Linse, S
影响因子：
2.9
作者：
Jourdan, M;Searle, MS
通讯作者：
Searle, MS
影响因子：
15
作者：
Linse, Sara;Linse, Bjorn
通讯作者：
Linse, Bjorn