... amplitude of the slow phase(extent of ligation) is independent of the concentration of ATP, approaching % 90% of the total concentration of thendsDNA substrate in the reaction mixture.Effect of Mg2+concentrationMg2+is ... member of the same superfamily of nucleotidyl-transferases [34,35]. In the cell, capping of the 5¢-end of mRNA ensures protection from degradation by specific exonucleases [36,37]. In the case of ... &Weiner, M. (1976) Transcriptional control of T4 coliphage -specific genes 30, 42, 43, RIIA, RIIB, and e. J. Gen. Virol. 31, 289–302.33. Traut, T.W. (1994) Physiological concentrations of purines andpyrimidines....