Kavunenko A P, Sidorova N S
Nucleic Acids Res. 1976 Apr;3(4):1073-9. doi: 10.1093/nar/3.4.1073.
The synthesis of uridylyl-(3'-5')-3-ribosyl-6-methyluracil (UprmU) catalyzed by pancreatic ribonuclease (EC 3.4.1.22) has been performed using uridine 2', 3'-cyclic phosphate (U greater than p) as phosphate donor and 3-ribosyl-6-methyluracil (rmU) as phosphate acceptor. The rate of synthesis of UprmU is much higher than that of uridylyl-(3'-5')-uridine (UpU) in a control experiment under the same conditions with uridine as acceptor. The yields of UpU and UprmU were 20 and 17% respectively. The competitive hydrolysis of the initial U greater than p also proceeds faster when rmU is used as the acceptor. The relationship between the conformation of this nucleoside and its acceptor activity in the enzymatic synthesis of the internucleotide bond is discussed.
利用2',3'-环磷酸尿苷(U>p)作为磷酸供体,3-核糖基-6-甲基尿嘧啶(rmU)作为磷酸受体,进行了由胰核糖核酸酶(EC 3.4.1.22)催化的尿苷酰基-(3'-5')-3-核糖基-6-甲基尿嘧啶(UprmU)的合成。在相同条件下以尿苷作为受体的对照实验中,UprmU的合成速率远高于尿苷酰基-(3'-5')-尿苷(UpU)。UpU和UprmU的产率分别为20%和17%。当使用rmU作为受体时,初始U>p的竞争性水解也进行得更快。讨论了该核苷的构象与其在核苷酸间键的酶促合成中的受体活性之间的关系。