Klee C B, Krinks M H
Biochemistry. 1978 Jan 10;17(1):120-6. doi: 10.1021/bi00594a017.
The Ca2+-dependent, reversible, interaction of cyclic adenosine 3',5'-monophosphate (cAMP) phosphodiesterase with its activator has been used to purify the enzyme by affinity chromatography. Activator-dependent cAMP phosphodiesterase is only a minor component of the proteins specifically adsorbed in the presence of Ca2+ by the Ca2+-dependent activator protein coupled to Sepharose and subsequently released by [ethylenebis(oxyethylenenitrilo)]tetraacetic acid. The major protein component can be partially resolved from the enzyme by gel filtration on Sephadex G-200. This protein has been purified to apparent homogeneity and shown to be composed of two polypeptide chains with molecular weights of 61,000 and 15,000 respectively. This protein is, by itself, devoid of phosphodiesterase activity and inhibits the activation of cAMP phosphodiesterase by its activator without affecting the basal activity. Thus, activation of cAMP phosphodiesteriase by the Ca2+-dependent activator protein may be controlled by interactions with yet a third component of the enzyme complex.
环磷酸腺苷（cAMP）磷酸二酯酶与其激活剂之间依赖于Ca2+的可逆相互作用已被用于通过亲和色谱法纯化该酶。依赖激活剂的cAMP磷酸二酯酶只是在Ca2+存在下被偶联到琼脂糖上的依赖Ca2+的激活蛋白特异性吸附并随后被[乙二胺双（氧乙烯腈）]四乙酸释放的蛋白质中的次要成分。主要蛋白质成分可以通过在Sephadex G - 200上进行凝胶过滤与该酶部分分离。这种蛋白质已被纯化至表观均一性，并显示由两条分别具有61,000和15,000分子量的多肽链组成。这种蛋白质本身没有磷酸二酯酶活性，并且在不影响基础活性的情况下抑制其激活剂对cAMP磷酸二酯酶的激活。因此，依赖Ca2+的激活蛋白对cAMP磷酸二酯酶的激活可能受与酶复合物的第三个成分相互作用的控制。
