McConkey E H
Proc Natl Acad Sci U S A. 1982 May;79(10):3236-40. doi: 10.1073/pnas.79.10.3236.
High-resolution two-dimensional polyacrylamide gel electrophoresis shows that at least half of 370 denatured polypeptides from hamster cells and human cells are indistinguishable in terms of isoelectric points and molecular weights. Molecular evolution may have been more conservative for this set of proteins than sequence studies on soluble proteins have implied. This may be a consequence of complexities of intracellular organization and the numerous macromolecular interactions in which most polypeptides participate. It is suggested that the term "quinary structure" be used to refer to macromolecular interactions that are transient in vivo. Such interactions will not be evident from the composition of purified proteins, but they may constitute an important source of constraints on changes in primary structure.
高分辨率二维聚丙烯酰胺凝胶电泳显示，仓鼠细胞和人类细胞的370种变性多肽中，至少有一半在等电点和分子量方面难以区分。对于这组蛋白质而言，分子进化可能比可溶性蛋白质的序列研究所暗示的更为保守。这可能是细胞内组织复杂性以及大多数多肽参与的众多大分子相互作用的结果。有人建议用“五元结构”一词来指代体内短暂存在的大分子相互作用。这种相互作用从纯化蛋白质的组成中不会明显体现，但它们可能是对一级结构变化构成限制的重要来源。
