• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Molecular Biology >High-Pressure NMR and SAXS Reveals How Capping Modulates Folding Cooperativity of the pp32 Leucine-rich Repeat Protein
【24h】

High-Pressure NMR and SAXS Reveals How Capping Modulates Folding Cooperativity of the pp32 Leucine-rich Repeat Protein

机译：高压NMR和萨克斯显示封盖如何调节PP32富含富氨酸的重复蛋白的折叠合作性

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Many repeat proteins contain capping motifs, which serve to shield the hydrophobic core from solvent and maintain structural integrity. While the role of capping motifs in enhancing the stability and structural integrity of repeat proteins is well documented, their contribution to folding cooperativity is not. Here we examined the role of capping motifs in defining the folding cooperativity of the leucine-rich repeat protein, pp32, by monitoring the pressure- and urea-induced unfolding of an N-terminal capping motif (N-cap) deletion mutant, pp32-Delta N-cap, and a C-terminal capping motif destabilization mutant pp32-Y131F/D146L, using residue-specific NMR and small-angle X-ray scattering. Destabilization of the C-terminal capping motif resulted in higher cooperativity for the unfolding transition compared to wild-type pp32, as these mutations render the stability of the C-terminus similar to that of the rest of the protein. In contrast, deletion of the N-cap led to strong deviation from two-state unfolding. In both urea and pressure-induced unfolding, residues in repeats 1-3 of pp32-Delta N-cap lost their native structure first, while the C-terminal half was more stable. The residue-specific free energy changes in all regions of pp32-Delta N-cap were larger in urea compared to high pressure, indicating a less cooperative destabilization by pressure. Moreover, in contrast to complete structural disruption of pp32-Delta N-cap at high urea concentration, its pressure unfolded state remained compact. The contrasting effects of the capping motifs on folding cooperativity arise from the differential local stabilities of pp32, whereas the contrasting effects of pressure and urea on the pp32-Delta N-cap variant arise from their distinct mechanisms of action. (C) 2018 Elsevier Ltd. All rights reserved.
机译：许多重复蛋白质含有封盖基序，用于保护疏水芯免受溶剂和保持结构完整性。虽然将图案提高重复蛋白质的稳定性和结构完整性的封装主题的作用得到了很好的记录，但它们对折叠合作效力的贡献不是。在这里，我们通过监测N-末端封端基序（N-CAP）缺失突变体，PP32-通过监测压力和尿素诱导的压力和尿素诱导的展开，研究了封装基序的作用。 Delta N-Cap，以及C末端封装基像稳定突变体PP32-Y131F / D146L，使用残留物的NMR和小角度X射线散射。与野生型PP32相比，C末端覆盖基质的稳定性转变导致展开转变的稳定性较高，因为这些突变使得C-末端类似于蛋白质其余部分的稳定性。相反，缺失n帽导致对两个状态展开的强烈偏差。在尿素和压力诱导的展开中，PP32-DELTA N-CAP的重复1-3中的残基首先丧失了它们的天然结构，而C末端半是更稳定的。与高压相比，尿素的所有区域的残基特异性自由能变化在尿素上较大，表明通过压力不太合作稳定。此外，与在高尿素浓度下PP32-DELTA N-帽的完全结构破坏相反，其压力展开状态仍然紧凑。从PP32的差异局部稳定性引起覆盖基序对折叠协作的对比作用，而压力和尿素对PP32-DELTA N-CAP变体的对比作用是从其不同的作用机制。 （c）2018年elestvier有限公司保留所有权利。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号