Abita J P, Milstien S, Chang N, Kaufman S
J Biol Chem. 1976 Sep 10;251(17):5310-4.
Essentially pure phenylalanine hydroxylase from rat liver can be activated between 2.5- and 3.0-fold by treatment with Mg2+, ATP, protein kinase, and cyclic AMP. The activation is seen when the hydroxylase is assayed in the presence of tetrahydrobiopterin, but not in the presence of 2-amino-4-hydroxy-6,7-dimethyltetrahydropteridine. In the presence of [gamma-32P]ATP, activation is accompanied by incorporation of 32P into the protein to the extent of 0.7 mol/mol of hydroxylase subunit (Mr = 50,000). Cehmical analysis of the untreated enzyme shows that it already contains about 0.3 mol of Pi/mol of hydroxylase. These results suggest that the activity of the hydroxylase may be regulated by phosphorylation.
来自大鼠肝脏的基本纯的苯丙氨酸羟化酶，通过用镁离子、ATP、蛋白激酶和环磷酸腺苷处理，可被激活2.5至3.0倍。当在四氢生物蝶呤存在的情况下测定羟化酶时可观察到这种激活，但在2-氨基-4-羟基-6,7-二甲基四氢蝶呤存在时则未观察到。在[γ-32P]ATP存在的情况下，激活伴随着32P掺入蛋白质中，掺入量为每摩尔羟化酶亚基（Mr = 50,000）0.7摩尔。对未处理的酶进行化学分析表明，它已经含有每摩尔羟化酶约0.3摩尔的无机磷酸。这些结果表明，羟化酶的活性可能受磷酸化作用调节。
