Guliaev N N, Tunitskaia V L, Nesterova M V, Mazurova L A, Murtuzaev I M
Biokhimiia. 1977 Nov;42(11):2071-8.
A synthesis of previously unknown 8-substituted derivatives and alkyl esters of cyclic adenosine-3',5'-monophosphate, containing reactive groups, was carried out. The interaction of the compounds obtained with a homogeneous preparation of protein kinase from pig brain was studied. It was found that all compounds, with the exception of neutral esters of 3',5'-AMP, activate the enzyme and competitively inhibit 3H-labelled 3',5'-cAMP binding by the regulatory subunit of protein kinase. The activating effect and affinity of 8-(beta-aminoethylamino)-3',5'-cAMP for protein kinase was 10 times lower than that for 3',5'-cAMP and other 8-substituted derivatives of the cyclic nucleotide. It was found that 8-(N-chloroacetylaminoethylamino)-3',5'-cAMP interaction with the enzyme is of irreversible type, which suggest covalent blocking of the nucleophilic group of the 3',5'-cAMP binding site of protein kinase. The data obtained indicate that the 3',5'-cAMP molecule is bound to the regulatory site of protein kinase in the syn-conformation. The previously made assumption on the crucial importance of the negative charge in the 3',5'-cyclophosphate system for the interaction of cyclic AMP with the regulatory subunit of protein kinase has been thus confirmed.
合成了含有反应基团的环腺苷 - 3',5'-单磷酸的8-取代衍生物和烷基酯，这些衍生物此前并不为人所知。研究了所得化合物与猪脑蛋白激酶的均一制剂之间的相互作用。结果发现，除了3',5'-AMP的中性酯外，所有化合物均能激活该酶，并竞争性抑制蛋白激酶调节亚基与3H标记的3',5'-cAMP的结合。8-(β-氨基乙氨基)-3',5'-cAMP对蛋白激酶的激活作用和亲和力比3',5'-cAMP及环核苷酸的其他8-取代衍生物低10倍。研究发现，8-(N-氯乙酰氨基乙氨基)-3',5'-cAMP与该酶的相互作用是不可逆的，这表明蛋白激酶3',5'-cAMP结合位点的亲核基团被共价阻断。所得数据表明，3',5'-cAMP分子以顺式构象与蛋白激酶的调节位点结合。因此，先前关于3',5'-环磷酸系统中的负电荷对环腺苷酸与蛋白激酶调节亚基相互作用至关重要的假设得到了证实。
