Komatsu-Takaki M
J Biol Chem. 1986 Jan 25;261(3):1116-9.
Chloroplast ATPase complex is activated by illumination in the presence or absence of dithiothreitol. ATPase complex which has been activated without dithiothreitol catalyzes ATP hydrolysis which is insensitive to stimulation by NH4Cl and is highly sensitive to medium pH. Addition of dithiothreitol during illumination results in an increase in the stimulating effect of NH4Cl on ATP hydrolysis and a decrease in pH sensitivity of ATP hydrolysis. With increasing time in the dark, the ability of NH4Cl to stimulate ATP hydrolysis decreases and the effect of pH on the ATP hydrolysis increases. The onset of resistance to NH4Cl stimulation and the increase in sensitivity to pH are accelerated by ADP and the acceleration is inhibited by Pi. ATP hydrolysis restores NH4Cl sensitivity and renders the activity more resistant to pH. These results suggest that active chloroplast ATPase complex converts its state reversibly from the NH4Cl-insensitive and highly pH-sensitive one to the NH4Cl-sensitive and relatively pH-insensitive one. The conversion from the former to the latter requires both sulfhydryl compound and energy.
叶绿体ATP酶复合体在有或没有二硫苏糖醇存在的情况下，均可被光照激活。在没有二硫苏糖醇的情况下被激活的ATP酶复合体催化ATP水解，这种水解对氯化铵的刺激不敏感，但对介质pH高度敏感。光照期间添加二硫苏糖醇会导致氯化铵对ATP水解的刺激作用增强，而ATP水解的pH敏感性降低。在黑暗中放置的时间越长，氯化铵刺激ATP水解的能力下降，pH对ATP水解的影响增加。ADP加速了对氯化铵刺激的抗性的出现以及对pH敏感性的增加，而无机磷酸则抑制了这种加速作用。ATP水解恢复了对氯化铵的敏感性，并使活性对pH更具抗性。这些结果表明，活性叶绿体ATP酶复合体可逆地将其状态从对氯化铵不敏感且对pH高度敏感的状态转变为对氯化铵敏感且对pH相对不敏感的状态。从前者到后者的转变既需要巯基化合物也需要能量。
