期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2002
卷号：99
期号：3
页码：1329-1334
DOI：10.1073/pnas.012458999
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：To investigate protein folding dynamics in terms of compactness, we developed a continuous-flow mixing device to make small-angle x-ray scattering measurements with the time resolution of 160 {micro}s and characterized the radius of gyration (Rg) of two folding intermediates of cytochrome c (cyt c). The early intermediate possesses {approx}20 A of Rg, which is smaller by {approx}4 A than that of the acid-unfolded state. The Rg of the later intermediate is {approx}18 A, which is close to that of the molten globule state. Considering the -helix content (fH) of the intermediates, we clarified the folding pathway of cyt c on the conformational landscape defined by Rg and fH. Cyt c folding proceeds with a collapse around a specific region of the protein followed by a cooperative acquisition of secondary structures and compactness.
