Predki P F, Agrawal V, Brünger A T, Regan L
Department of Molecular Biophysics and Biochemistry Yale University, New Haven, Connecticut 06520, USA.
Nat Struct Biol. 1996 Jan;3(1):54-8. doi: 10.1038/nsb0196-54.
A surface turn position in a four-helix bundle protein, Rop, was selected to investigate the role of turns in protein structure and stability. Although all twenty amino acids can be substituted at this position to generate a correctly folded protein, they produce an unusually large range of thermodynamic stabilities. Moreover, the majority of substitutions give rise to proteins with enhanced thermal stability compared to that of the wild type. By introducing the same twenty mutations at this position, but in a simplified context, we were able to deconvolute intrinsic preferences from local environmental effects. The intrinsic preferences can be explained on the basis of preferred backbone dihedral angles, but local environmental context can significantly modify these effects.
在四螺旋束蛋白Rop中选择了一个表面转角位置，以研究转角在蛋白质结构和稳定性中的作用。尽管在此位置可以替换所有20种氨基酸以产生正确折叠的蛋白质，但它们产生的热力学稳定性范围异常大。此外，与野生型相比，大多数替换产生的蛋白质具有更高的热稳定性。通过在这个位置引入相同的20种突变，但在一个简化的背景下，我们能够从局部环境效应中解卷积内在偏好。内在偏好可以基于优选的主链二面角来解释，但局部环境背景可以显著改变这些效应。
