Schwarzinger Stephan, Wright Peter E, Dyson H Jane
Department of Molecular Biology and Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California 92037, USA.
Biochemistry. 2002 Oct 22;41(42):12681-6. doi: 10.1021/bi020381o.
Unfolded apomyoglobin in 8 M urea at pH 2.3 displays distinct regions with different backbone mobility, as monitored by NMR relaxation. These variations in backbone mobility can be correlated with intrinsic properties of the amino acids in the sequence. Clusters of small amino acids such as glycine and alanine show increased backbone mobility compared to the average. In contrast, local hydrophobic interactions that persist in urea denaturant cause some restriction of backbone motions on a picosecond to nanosecond time scale. The model derived from the behavior of apoMb in urea depends only on the most fundamental properties of the local amino acid sequence, and thus provides a feasible paradigm for the initiation of folding.
在pH 2.3的8 M尿素中展开的脱辅基肌红蛋白，通过核磁共振弛豫监测，显示出具有不同主链流动性的不同区域。主链流动性的这些变化可以与序列中氨基酸的内在特性相关联。与平均值相比，诸如甘氨酸和丙氨酸等小氨基酸簇显示出增加的主链流动性。相反，在尿素变性剂中持续存在的局部疏水相互作用在皮秒到纳秒的时间尺度上导致主链运动的一些限制。从脱辅基肌红蛋白在尿素中的行为推导出来的模型仅取决于局部氨基酸序列的最基本特性，因此为折叠的起始提供了一个可行的范例。
