Lent B A, Kim K H
Arch Biochem Biophys. 1983 Sep;225(2):972-8. doi: 10.1016/0003-9861(83)90113-3.
The catalytic subunit of cyclic AMP-dependent protein kinase stimulates the inactivation of acetyl-coenzyme A (CoA) carboxylase by acetyl-CoA carboxylase kinase. The stimulated inactivation of carboxylase is due to activation of carboxylase kinase by the catalytic subunit. Activation of carboxylase kinase activity is accompanied by the incorporation of 0.6 mol of phosphate per mole of carboxylase kinase. Addition of the regulatory subunit of cyclic AMP-dependent protein kinase prevents the activation of carboxylase kinase. Phosphorylation and activation of carboxylase kinase has no effect on the Km for ATP, but decreases the Km for acetyl-CoA carboxylase from 93 to 45 nM. Inactivation of carboxylase by the carboxylase kinase requires the presence of coenzyme A even when the activated carboxylase kinase is used. Acetyl-CoA carboxylase is not phosphorylated or inactivated by the catalytic subunit of cyclic AMP-dependent protein kinase.
环磷酸腺苷依赖性蛋白激酶的催化亚基通过乙酰辅酶A羧化酶激酶刺激乙酰辅酶A（CoA）羧化酶的失活。羧化酶的这种被刺激的失活是由于催化亚基激活了羧化酶激酶。羧化酶激酶活性的激活伴随着每摩尔羧化酶激酶掺入0.6摩尔磷酸盐。添加环磷酸腺苷依赖性蛋白激酶的调节亚基可阻止羧化酶激酶的激活。羧化酶激酶的磷酸化和激活对ATP的Km没有影响，但使乙酰辅酶A羧化酶的Km从93 nM降至45 nM。即使使用活化的羧化酶激酶，羧化酶激酶使羧化酶失活也需要辅酶A的存在。环磷酸腺苷依赖性蛋白激酶的催化亚基不会使乙酰辅酶A羧化酶磷酸化或失活。
