Nakamoto H, Edwards G E
Biochem Biophys Res Commun. 1983 Sep 15;115(2):673-9. doi: 10.1016/s0006-291x(83)80197-1.
Pyruvate, Pi dikinase, which is localized in the mesophyll chloroplasts of C4 plants, requires a high adenylate energy charge for conversion of the enzyme from the inactive to the active form. The inactivation process is favored by a low energy charge, being maximal at values below 0.7. Pyruvate and analogs of pyruvate, oxamate and oxalate, strongly inhibit the inactivation process at millimolar levels. The results suggest that light activation of the enzyme in vivo may be mediated by an increased adenylate energy charge in the chloroplast. Pyruvate may allow a higher steady-state level of activation to be achieved in vivo by inhibiting inactivation.
丙酮酸磷酸双激酶定位于C4植物的叶肉叶绿体中，该酶从无活性形式转变为活性形式需要较高的腺苷酸能荷。低能荷有利于失活过程，在能量荷值低于0.7时失活作用最大。丙酮酸以及丙酮酸类似物草氨酸盐和草酸盐在毫摩尔浓度水平时能强烈抑制失活过程。结果表明，该酶在体内的光激活可能由叶绿体中腺苷酸能荷的增加介导。丙酮酸可能通过抑制失活作用，使体内达到更高的稳态激活水平。
