Colosimo A, Brunori M, Antonini E
Biochem J. 1976 Mar 1;153(3):657-61. doi: 10.1042/bj1530657.
Horse heart cytochrome c was covalently bound to Sepharose 4B and its redox properties were measured under various experimental conditions. The equilibrium constant for the electron exchange between the oxidized and the reduced form of cytochrome c when one of the two forms was in the semi-solid state and the other one in solution was close to 1. Matrix-bound ferrocytochrome c is very stable to autoxidation and is not oxidized by O2 even in the presence of mammalian cytochrome oxidase. Oxidation occurs if catalytic amounts of soluble cytochrome c are added to the reaction mixture. The rate of oxidation of matrix-bound ferrocytochrome c in the presence of cytochrome oxidase and catalytic amounts of soluble cytochrome c may be correlated with the rate of electron transfer between soluble and matrix-bound cytochrome c. This rate is more than two orders of magnitude lower than that reported for the homonuclear (between identical species) electron transfer in solution.
马心脏细胞色素c被共价结合到琼脂糖4B上，并在各种实验条件下测量其氧化还原特性。当细胞色素c的氧化型和还原型中的一种处于半固态而另一种处于溶液状态时，它们之间电子交换的平衡常数接近1。基质结合的亚铁细胞色素c对自氧化非常稳定，即使在存在哺乳动物细胞色素氧化酶的情况下也不会被O2氧化。如果向反应混合物中加入催化量的可溶性细胞色素c，就会发生氧化。在细胞色素氧化酶和催化量的可溶性细胞色素c存在的情况下，基质结合的亚铁细胞色素c的氧化速率可能与可溶性和基质结合的细胞色素c之间的电子转移速率相关。该速率比溶液中同核（相同物种之间）电子转移报道的速率低两个数量级以上。
