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：1978
卷号：75
期号：2
页码：554-558
DOI：10.1073/pnas.75.2.554
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：In this paper we carry out computer simulation studies of some of the factors responsible for protein tertiary structure. We show that it is possible to obtain (fold) a compact globular conformation from a sequence of amino acids consisting of only glycines and alanines. Our results indicate that glycines play a central role in stabilizing globular structures by facilitating the formation of turns and by destabilizing helical structures. Using this simple two-amino-acid representation, which serves as a control experiment, we are able to obtain a conformation that resembles the native structure of pancreatic trypsin inhibitor, as closely as any obtained previously in folding studies. However, careful examination reveals that the true chain topology has not been reproduced here or in previous studies. We suggest that the discrepancies between calculated and observed structures are more significant than the similarities. The implications of these results for the validity of models for protein folding, the use of pancreatic trypsin inhibitor in folding studies, and the possible role of glycine in the evolution of protein structure are discussed.
