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：2017
卷号：114
期号：34
页码：9014-9019
DOI：10.1073/pnas.1706825114
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The formation of quasi-spherical cages from protein building blocks is a remarkable self-assembly process in many natural systems, where a small number of elementary building blocks are assembled to build a highly symmetric icosahedral cage. In turn, this has inspired synthetic biologists to design de novo protein cages. We use simple models, on multiple scales, to investigate the self-assembly of a spherical cage, focusing on the regularity of the packing of protein-like objects on the surface. Using building blocks, which are able to pack with icosahedral symmetry, we examine how stable these highly symmetric structures are to perturbations that may arise from the interplay between flexibility of the interacting blocks and entropic effects. We find that, in the presence of those perturbations, icosahedral packing is not the most stable arrangement for a wide range of parameters; rather disordered structures are found to be the most stable. Our results suggest that ( i ) many designed, or even natural, protein cages may not be regular in the presence of those perturbations and ( ii ) optimizing those flexibilities can be a possible design strategy to obtain regular synthetic cages with full control over their surface properties.
关键词：coarse-grained modeling ; icosahedral symmetry ; protein cage ; self-assembly ; protein design
