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：1990
卷号：87
期号：15
页码：5648-5652
DOI：10.1073/pnas.87.15.5648
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The environments of metal ions (Li+, Na+, K+, Ag+, Cs+, Mg2+, Ca2+, Mn2+, Cu2+, Zn2+) in proteins and other metal-host molecules have been examined. Regardless of the metal and its precise pattern of ligation to the protein, there is a common qualitative feature to the binding site: the metal is ligated by a shell of hydrophilic atomic groups (containing oxygen, nitrogen, or sulfur atoms) and this hydrophilic shell is embedded within a larger shell of hydrophobic atomic groups (containing carbon atoms). That is, metals bind at centers of high hydrophobicity contrast. This qualitative observation can be described analytically by the hydrophobicity contrast function, C, evaluated from the structure. This function is large and positive for a sphere of hydrophilic atomic groups (characterized by atomic solvation parameters, delta sigma, having values less than 0) at the center of a larger sphere of hydrophobic atomic groups (characterized by delta sigma greater than 0). In the 23 metal-binding molecules we have examined, the maximum values of the contrast function lie near to observed metal binding sites. This suggests that the hydrophobicity contrast function may be useful for locating, characterizing, and designing metal binding sites in proteins.
