Mechanism of the reaction of tryptophanyl transfer rna formation catalyzed by tryptophanyl transfer rna synthetase
Kochkina, L.L.; Akhverdyan, V.Z.; Kiselev, L.L.; Zinov'ev, V.V.; Malygin, E.G.
Molekulyarnaya Biologiya (Moscow) 10(2): 437-444
The rates of tryptophanyl-tRNA formation catalyzed by beef pancreas tryptophanyl-tRNA synthetase were measured in a concentration range of each substrate (tryptophan ATP and yeast tRNATrp) and also in the presence of various concentrations of substrate analogues (tryptamine and .alpha.,.beta.-methylene analogue of ATP) concentrations. The data obtained were compared with the kinetic equations which described various possible mechanisms of the reaction. The comparison of the mechanisms was based on the calculation of relative probabilities of each hypothesis the efficiency of which was demonstrated earlier. The calculations have shown that 2 mechanisms according to which the intermediate enzyme-aminoacyl-adenylate complex formation involves the enzyme-aminoacyl-tRNA complex are the most probable ones.