爱魔域

大多数天然α-氨基酸的铜络合物的稳定性常数是已知的。然而，迅雷魔域boss尽管它具有相当大的生化意义，但铜-组氨酸系统尚未得到详细解释。该系统是异常的，可能是因为尽管金属可以与组氨酸中的氨基、咪唑或羧基配位，但铜配合物的假定平面构型只允许任何组氨酸分子中的两个位点同时结合 1。通过这种方式，组氨酸阴离子 (L-) 和两性离子 (HL+-) 都可以作为螯合物质，产生五种不同的复合物，CuL+、CuHL++、CuL2、CuHL2+ 和 Cu(HL)2++。由于 L- 与 HL+- 的浓度比取决于 pH 值，因此存在的复合物比例将随配体浓度和 pH 值而变化。

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Histidine-Copper (II) Complexes

STABILITY constants are known for copper complexes of most of the naturally occurring α-amino-acids. However, although it is of considerable biochemical interest, the copper–histidine system has not been interpreted in detail. The system is anomalous, probably because, although the metal can co-ordinate to the amino, imidazole or carboxyl groups in histidine, an assumed planar configuration of the cupric complexes allows only two sites in any histidine molecule to be bound simultaneously1. In this way both the histidine anion (L−) and the zwitterion (HL+−) can act as chelating species, giving the five different complexes, CuL+, CuHL++, CuL2, CuHL2+ and Cu(HL)2++. Because the concentration ratio of L− to HL+− is dependent on pH, the proportions of the complexes present will vary with both ligand concentration and pH.