Structure of pressure-assisted cold denatured lysozyme and comparison with lysozyme folding intermediates.
Structure of pressure-assisted cold denatured lysozyme and comparison with lysozyme folding intermediates.
复制标题
压力辅助冷变性溶菌酶的结构及其与溶菌酶折叠中间体的比较。
DOI：
10.1021/bi970881v
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发表时间：
1997
期刊：
影响因子：
--
通讯作者：
Jonas,J
中科院分区：
文献类型：
--
作者：
Nash,DP;Jonas,J
在高（bb0 - 3.5 kbar）压力和低（< - 10°C）温度下，蛋清溶菌酶容易可逆地变性。采用酰胺氢交换法研究了溶菌酶的压力辅助冷变性结构。得到52个主酰胺质子的保护因子。这些质子的保护程度与高温、高尿素浓度或化学修饰的溶菌酶的保护程度明显不同；具体来说，保护因子更高，并且与原生状态中存在的二级结构元素密切相关。此外，保护因子的模式与溶菌酶在从高度变性状态重折叠过程中观察到的相似，特别是在重折叠的早期阶段（<3.5 ms） [Gladwin， S. T., & Evans， P. A. (1996)Folding Des.1, 407]。先前关于冷变性核糖核酸酶A的数据被重新评估并与已知的折叠中间体进行比较[Houry， W. A., & Scheraga， H. A. (1996)Biochemistry35, 11734；Udgaonkar， J. B, & Baldwin， R. L. (1990)Proc。Natl.Acad。科学。U.S.A.87, 8197]以进一步验证蛋白质的压力辅助冷变性状态类似于早期折叠阶段的假设。
At high (>3.5 kbar) pressures and low (<−10 °C) temperatures, hen egg-white lysozyme denatures readily and reversibly. Amide hydrogen exchange methods were used to investigate the structure of the pressure-assisted cold-denatured state of lysozyme. Protection factors were obtained for 52 backbone amide protons. The extent of protection of many of these protons is markedly different from that in lysozyme denatured by high temperature, high urea concentration, or chemical modification; specifically, the protection factors are higher and are strongly correlated with elements of secondary structure present in the native state. Furthermore, the pattern of protection factors is similar to that observed in lysozyme during refolding from highly denatured states, particularly during the early stages (<3.5 ms) of refolding [Gladwin, S. T., & Evans, P. A. (1996)Folding Des.1, 407]. Previous data on cold-denatured ribonuclease A were reevaluated and compared to known folding intermediates [Houry, W. A., & Scheraga, H. A. (1996)Biochemistry35, 11734; Udgaonkar, J. B., & Baldwin, R. L. (1990)Proc. Natl.Acad. Sci. U.S.A.87, 8197] to further test the supposition that the pressure-assisted cold-denatured states of proteins resemble the early folding stages.