Dooley D M, Golnik K C
J Biol Chem. 1983 Apr 10;258(7):4245-8.
The role of copper in pig kidney diamine oxidase has been probed by examining the effects of potential Cu(II) ligands on the spectroscopic and catalytic properties of the enzyme. In the presence of azide and thiocyanate, new absorption bands are evident at 410 nm (epsilon = 6300 M-1 cm-1) and 365 nm (epsilon = 3000 M-1 cm-1), respectively. These bands are assigned as ligand-to-metal charge-transfer transitions, N3-/SCN- leads to Cu(II). One anion/Cu(II) is coordinated in an equitorial position. Anion binding can be completely reversed by dialysis. The equilibrium constants for diamine oxidase-anion complex formation are 134 M-1 (N3-) and 55 M-1 (SCN-). Azide and thiocyanate are linear uncompetitive inhibitors with respect to the amine substrate when O2 is present at saturating concentrations. Taken together, the data are consistent with a functional role for Cu(II) in diamine oxidase catalysis.
通过研究潜在的Cu(II)配体对猪肾二胺氧化酶光谱和催化性质的影响，对铜在该酶中的作用进行了探究。在叠氮化物和硫氰酸盐存在的情况下，分别在410 nm（ε = 6300 M-1 cm-1）和365 nm（ε = 3000 M-1 cm-1）处出现明显的新吸收带。这些吸收带被归为配体到金属的电荷转移跃迁，即N3-/SCN-与Cu(II)发生作用。一个阴离子/Cu(II)在赤道位置配位。阴离子结合可通过透析完全逆转。二胺氧化酶-阴离子复合物形成的平衡常数分别为134 M-1（N3-）和55 M-1（SCN-）。当O2以饱和浓度存在时，叠氮化物和硫氰酸盐对于胺底物而言是线性非竞争性抑制剂。综合来看，这些数据与Cu(II)在二胺氧化酶催化中的功能作用相一致。
