Stevens T H, Martin C T, Wang H, Brudvig G W, Scholes C P, Chan S I
J Biol Chem. 1982 Oct 25;257(20):12106-13.
The isolation and purification of yeast cytochrome c oxidase is described. Characterization of the purified protein indicates that it is spectroscopically identical with cytochrome c oxidase isolated from beef heart. Preparations of isotopically substituted yeast cytochrome c oxidase are obtained incorporating [1,3-15N2]histidine or [beta,beta-2H2]cysteine. Electron paramagnetic resonance and electron nuclear double resonance spectra of the isotopically substituted proteins identify unambiguously at least 1 cysteine and 1 histidine as ligands to CuA and suggest that substantial spin density is delocalized onto a cysteine sulfur in the oxidized protein to render the site Cu(I)--S.
本文描述了酵母细胞色素c氧化酶的分离与纯化。对纯化蛋白的表征表明，其在光谱上与从牛心分离得到的细胞色素c氧化酶相同。通过掺入[1,3-¹⁵N₂]组氨酸或[β,β-²H₂]半胱氨酸获得了同位素取代的酵母细胞色素c氧化酶制剂。同位素取代蛋白的电子顺磁共振和电子核双共振光谱明确鉴定出至少1个半胱氨酸和1个组氨酸作为CuA的配体，并表明在氧化蛋白中大量的自旋密度离域到半胱氨酸硫上，使该位点成为Cu(I)--S。
