Ozawa T, Suzuki H, Tanaka M
Proc Natl Acad Sci U S A. 1980 Feb;77(2):928-30. doi: 10.1073/pnas.77.2.928.
Cytochrome c oxidase (ferrocytochrome c oxygen oxidoreductase, EC 1.9.3.1) was purified from beef heart mitochondria by affinity chromatography. Phospholipids were removed by washing the oxidase with detergent on the affinity column; 1 mole of cardiolipin remained per mole of heme a. The oxidase was mixed with excess cytochrome c in 1.5% (wt/vol) cholate to form a complex. Slow removal of the detergent from the mixture by dialysis resulted in crystallization of cytochrome oxidase in the form of a 1:1 complex with cytochrome c. The chemical composition and spectrophotometric properties of the crystal are described. Increasing the solubility of a hydrophobic membrane protein by combination with hydropholic ligand is demonstrated as a maneuver for crystallizing the membrane protein.
细胞色素c氧化酶（亚铁细胞色素c氧氧化还原酶，EC 1.9.3.1）通过亲和色谱法从牛心线粒体中纯化得到。通过在亲和柱上用去污剂洗涤氧化酶来去除磷脂；每摩尔血红素a保留1摩尔心磷脂。将氧化酶与过量的细胞色素c在1.5%（重量/体积）胆酸盐中混合形成复合物。通过透析缓慢从混合物中去除去污剂导致细胞色素氧化酶以与细胞色素c的1:1复合物形式结晶。描述了晶体的化学组成和分光光度性质。通过与亲水配体结合来增加疏水膜蛋白的溶解度被证明是使膜蛋白结晶的一种策略。
