Effects of proline mutations on the unfolding and refolding of human lysozyme: the slow refolding kinetic phase does not result from proline cis-trans isomerization.
Effects of proline mutations on the unfolding and refolding of human lysozyme: the slow refolding kinetic phase does not result from proline cis-trans isomerization.
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脯氨酸突变对人溶菌酶展开和重折叠的影响：缓慢的重折叠动力学阶段不是由脯氨酸顺反异构化引起的。
DOI：
10.1021/bi00105a011
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发表时间：
1991
期刊：
影响因子：
2.9
通讯作者：
M. Kikuchi
中科院分区：
文献类型：
--
作者：
T. Herning;K. Yutani;Y. Taniyama;M. Kikuchi
展开和重折叠动力学的六个脯氨酸突变体的人溶菌酶（h-溶菌酶）进行了比较，野生型蛋白质。我们的研究结果表明，在h-溶菌酶复性动力学中观察到的缓慢复性阶段不能归因于脯氨酸异构化反应。h-溶菌酶在位置71和103处含有两个脯氨酸残基，两者在天然状态下均处于反式构象。P71 G/P103 G突变体的重折叠动力学，其中两个脯氨酸已被替换为甘氨酸，被发现是类似的野生型蛋白质。两种蛋白质的慢相振幅约为10%，慢相速率常数在实验误差范围内也相同。其他突变体，如P103 G或P71 G，其中只有一个的两个脯氨酸已被替换为甘氨酸，和A47 P与它的三个脯氨酸，给出了相同的缓慢重折叠阶段。每种蛋白质的X射线结构分析和扫描微量热研究（Herning et al.，未公开的实验）已经证实，所考虑的突变都没有显著影响蛋白质结构，并且这些突变没有引起蛋白质稳定性的重大变化。因此，比较突变体和野生型蛋白质的性质是合理的。有趣的是，V110 P突变体的重折叠动力学，其中脯氨酸残基已被引入位置110（α-螺旋的N-末端），显然是三相的。对于这个突变体的一个额外的非常缓慢的阶段，检测到的性质类似于那些预期从脯氨酸假说。对每种蛋白质进行了平衡变性研究，并部分介绍了h-溶菌酶的复性途径。我们还讨论了脯氨酸突变对h-溶菌酶在水中折叠途径的能量学的影响。
The unfolding and refolding kinetics of six proline mutants of the human lysozyme (h-lysozyme) were carried out and compared to that of the wild-type protein. Our results show that the slow refolding phase observed in the h-lysozyme refolding kinetics cannot be ascribed to proline isomerization reactions. The h-lysozyme contains two proline residues at positions 71 and 103, both in the trans conformation in the native state. The refolding kinetics of the P71G/P103G mutant, in which both prolines have been replaced by a glycine, were found to be similar to those of the wild-type protein. The same slow phase amplitude of about 10% was found for both proteins, and the slow phase rate constants were also identical within experimental error. Other mutants such as P103G or P71G, in which only one of the two prolines has been replaced by a glycine, and A47P with its three prolines, gave identical slow refolding phases. The X-ray structure analysis and scanning microcalorimetric study of each protein (Herning et al., unpublished experiments) have confirmed that none of the considered mutations affects significantly protein structure and that no major changes in protein stability were brought about by these mutations. Therefore, comparison of the properties of the mutant and wild-type proteins is legitimate. Interestingly, the refolding kinetics of the V110P mutant, in which a proline residue has been introduced at position 110 (N-terminus of an alpha-helix), were clearly triphasic. For this mutant an additional very slow phase with properties similar to those expected from the proline hypothesis was detected. Equilibrium denaturation studies were conducted for each protein, and the refolding pathway of h-lysozyme is partly presented. We also discuss the effect of proline mutations on the energetics of the folding pathway of the h-lysozyme in water.
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通过替换保守的脯氨酸残基，突变体 iso-2-细胞色素 c 的构象变化和缓慢的重折叠动力学。
影响因子：
2.9
作者：
White,TB;Berget,PB;Nall,BT
通讯作者：
Nall,BT
影响因子：
2.9
作者：
PACE, CN;LAURENTS, DV;THOMSON, JA
通讯作者：
THOMSON, JA
取代脯氨酸 71 的 iso-1-细胞色素 c 突变体形式的折叠/解折叠动力学。
影响因子：
2.9
作者：
Ramdas,L;Nall,BT
通讯作者：
Nall,BT
DOI：
10.1073/pnas.84.19.6663
发表时间：
1987-10-01
影响因子：
11.1
作者：
MATTHEWS, BW;NICHOLSON, H;BECKTEL, WJ
通讯作者：
BECKTEL, WJ
保守脯氨酸的替换消除了吸光度检测到的 iso-2-细胞色素 c 的慢折叠阶段。
影响因子：
2.9
作者：
Wood,LC;White,TB;Ramdas,L;Nall,BT
通讯作者：
Nall,BT