Low-temperature kinetics of the reaction of oxygen and solubilized cytochrome oxidase.
Low-temperature kinetics of the reaction of oxygen and solubilized cytochrome oxidase.
复制标题
氧和溶解的细胞色素氧化酶反应的低温动力学。
DOI：
10.1042/bj1710787
复制
发表时间：
1978
期刊：
影响因子：
--
通讯作者：
T. King
中科院分区：
文献类型：
--
作者：
B. Chance;C. Saronio;J. Leigh;W. Ingledew;T. King
溶解的细胞色素氧化酶在完全还原状态下与 O2 在低温下的反应揭示了与膜结合氧化酶观察到的特征相似的成分，即化合物 A 和 B，被认为分别是“氧”和“过氧”化合物。在溶解型氧化酶和膜结合型氧化酶中均发现了相似的种类；与膜结合物质相比，溶解制剂中与 O2 反应的反应速度常数和解离常数降低了 2-3 倍，因为前者对 O2 的反应性降低。以混合价态制备的氧化酶显示出在膜结合氧化酶中鉴定出的化合物C的独特吸收带特征。 alpha、beta、gamma 和近红外的分配制作了这些化合物可能的价态的吸收带。
The reaction of solubilized cytochrome oxidase in the fully reduced state with O2 at low temperatures reveals components with characteristics similar to those observed with the membrane-bound oxidase, namely compounds A and B, which are proposed to be 'oxy' and 'peroxy' compounds respectively. Similar species are identified in both solubilized and membrane-bound oxidases; the reaction velocity constant for the reation with O2 and the dissociation constant are decreased 2-3-fold in the solubilied preparation as compared with the membrane-bound species, owing to decreased reactivity towards O2 in the former. The oxidase prepared in the mixed-valence state shows the distinctive absorption band characteristic of compound C, identified in the membrane-bound oxidase. The assignment of the alpha, beta, gamma and near-i.r. absorption bands to possible valence states of these compounds is made.