Stellwagen E, Cass R D
J Biol Chem. 1975 Mar 25;250(6):2095-8.
Electrostatic binding of at least two anionic iron hexacyanides to cationic horse heart cytochrome c was demonstrated by equilibrium dialysis measurements. No binding was detected following trifluoroacetylation of all of the 19 lysine residues. Replacement of the natural heme iron ligand methionine 80 by the alternative intrinsic ligand lysine 79 but not the extrinsic ligand imidazole resulted in the loss of one hexacyanide binding site. It is proposed that this site is located at the exposed heme edge and is functional in electron exchange.
通过平衡透析测量证明了至少两种阴离子铁氰化物与阳离子马心细胞色素c的静电结合。对所有19个赖氨酸残基进行三氟乙酰化后未检测到结合。用替代的内在配体赖氨酸79取代天然血红素铁配体甲硫氨酸80，但不是外在配体咪唑，导致一个铁氰化物结合位点的丧失。有人提出，该位点位于暴露的血红素边缘，在电子交换中起作用。
