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:1982
卷号:79
期号:18
页码:5734-5738
DOI:10.1073/pnas.79.18.5734
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Two models of protein-folding pathways are proposed on the basis of equilibrium and kinetic data in the literature. One is a growth-type model--i.e., nucleation of the native-like structure occurs in the folding process, in the rate-limiting step(s), and subsequent folding around the nucleation sites proceeds smoothly to form the native disulfide bonds and conformation. The other is a rearrangement-type model--i.e., proper nucleation does not occur in the folding process; instead, non-native interactions play a significant role in the folding pathways and lead to metastable intermediate species. Such non-native interactions, including incorrect disulfide bonds and proline cis-trans isomerization, must be disrupted or rearranged to nucleate the native interactions [a process that is included in the rate-limiting step(s)] for the protein to fold. The rate-limiting steps in the pathways for regeneration of RNase A from the reduced protein are classified as growth- or rearrangement-type pathways. The growth-type pathway is the one accompanying the formation of an intramolecular disulfide bond in the rate-limiting step. The rearrangement-type pathway is the one accompanying the reshuffling or disruption of a disulfide bond in the rate-limiting step. The folding of other proteins, accompanying oxidation of the reduced form, and the folding of denatured proteins with intact disulfide bonds are discussed in terms of the growth- and rearrangement-type models.