Malatesta F, Antonini G, Sarti P, Brunori M
Department of Experimental Medicine and Biochemical Sciences, University of Rome Tor Vergata, Italy.
Biochem J. 1987 Nov 15;248(1):161-5. doi: 10.1042/bj2480161.
The activity of cytochrome oxidase reconstituted into phospholipid vesicles has been studied as a function of orthophosphate, ATP and inositol hexakisphosphate concentrations. The respiratory-control ratio was found to be quite sensitive to these compounds and was inversely related to the anion concentration. This effect is related to a phosphate-dependent decrease in the rate constant for ferrocytochrome c oxidation observed in the presence of ionophores. The data cannot be interpreted simply on the basis of ionic strength, which is known to limit cytochrome c binding to cytochrome oxidase, since cytochrome oxidase-containing vesicles responded differently to phosphate depending on the energization state of the phospholipid membrane.
已对重构于磷脂囊泡中的细胞色素氧化酶的活性作为正磷酸盐、ATP和肌醇六磷酸浓度的函数进行了研究。发现呼吸控制率对这些化合物相当敏感，且与阴离子浓度呈负相关。这种效应与在离子载体存在下观察到的亚铁细胞色素c氧化速率常数的磷酸盐依赖性降低有关。这些数据不能仅基于离子强度来解释，因为已知离子强度会限制细胞色素c与细胞色素氧化酶的结合，因为含细胞色素氧化酶的囊泡根据磷脂膜的能量化状态对磷酸盐的反应不同。
