Skov K A, Vonderschmitt D J
Bioinorg Chem. 1975 Apr;4(3):199-213. doi: 10.1016/s0006-3061(00)80103-9.
The effects of oxidant, pH and ligands on iron- and copper-catalyzed ascorbate oxidation have been examined. The formation of the catalyst-substrate complex is affected by pH, whereas oxidant affects its breakdown. With copper-ion catalysis, ligands inhibit competitively. With iron catalysis, on the other hand, for a series of aminopolycarboxylic ligands at neutral pH, formation of catalyst-substrate is favored by ligands which form more stable iron complexes. Decreased rates caused by changes in metal environment (ligand or pH) may result for competing activities (e.g., catalase activity competing with peroxidase activity). Evidence for a ternary complex (catalyst-substrate-oxidant) is presented.
已研究了氧化剂、pH值和配体对铁和铜催化的抗坏血酸氧化的影响。催化剂-底物复合物的形成受pH值影响，而氧化剂影响其分解。在铜离子催化下，配体具有竞争性抑制作用。另一方面，在铁催化下，对于一系列中性pH值的氨基多羧酸配体，形成更稳定铁络合物的配体有利于催化剂-底物的形成。金属环境（配体或pH值）变化导致的反应速率降低可能是由于竞争活性（例如，过氧化氢酶活性与过氧化物酶活性竞争）。文中给出了三元复合物（催化剂-底物-氧化剂）的证据。
