Darby N J, van Mierlo C P, Scott G H, Neuhaus D, Creighton T E
MRC Laboratory of Molecular Biology, Cambridge, England.
J Mol Biol. 1992 Apr 20;224(4):905-11. doi: 10.1016/0022-2836(92)90458-v.
The most productive folding pathway of reduced bovine pancreatic trypsin inhibitor (BPTI) proceeds through the disulphide intermediates (30-51), (30-51, 5-14), and (30-51, 5-38); these are important kinetic intermediates in folding, even though the latter pair contain non-native disulphide bonds. Analogues of these intermediates have been prepared by protein engineering methods and their conformational properties examined by circular dichroism and 1H-nuclear magnetic resonance. The (30-51), (30-51, 5-14) and (30-51, 5-38) analogues exhibit comparable degrees of stable structure, which cannot include those portions of the polypeptide chain involving Cys5, Cys14 and Cys38. These properties are consistent with the roles of (30-51, 5-14) and (30-51, 5-38) in the folding pathway of BPTI, which demand that they exhibit a considerable degree of conformational flexibility in part of the molecule.
还原型牛胰蛋白酶抑制剂（BPTI）最有效的折叠途径是通过二硫键中间体（30 - 51）、（30 - 51，5 - 14）和（30 - 51，5 - 38）进行的；这些是折叠过程中重要的动力学中间体，尽管后一对中间体包含非天然二硫键。通过蛋白质工程方法制备了这些中间体的类似物，并通过圆二色性和1H - 核磁共振研究了它们的构象性质。（30 - 51）、（30 - 51，5 - 14）和（30 - 51，5 - 38）类似物表现出相当程度的稳定结构，其中不包括多肽链中涉及半胱氨酸5、半胱氨酸14和半胱氨酸38的部分。这些性质与（30 - 51，5 - 14）和（30 - 51，5 - 38）在BPTI折叠途径中的作用一致，这要求它们在分子的一部分中表现出相当程度的构象灵活性。
