Interactions of Zn(II) with single and multiple amino acids. Insights from density functional and ab initio calculations.

摘要: Calculations were performed to study the interactions of metal ions (M) with (multiple) amino acids (AA) and fill gap between single AA proteins. A complete conformational search results in nine eleven ZnGly isomers at B3P86 MP2 levels, respectively, four populated conformers glycine are responsible for production these isomers. For all M, via OO NO binding modes main constituents, mode is favored by stronger electrostatic interactions. Binding more glycines causes larger structural distortions, improves relative stabilities monodentate generates new (e.g. ZnB(III) only hydroxyl group). The scaling factor Zn(Gly)(n) structures, ratio its affinity versus sum comprising isomers, linear number (n), relationship may not be altered mutations M. It thus allows estimate M(AA)(n) affinities (n ≥ 2) from MAA structures analyze their kinetic methods. DFT become comparable increasing coordination, e.g. ZnA(I) (zwitterionic) energy differs 41.9 kcal mol(-1) levels close addition three water molecules (4.1 mol(-1)). presence solvent a broader distribution.