[The use of immobilized enzymes for the synthesis of nucleosides and nucleotides including the ones labeled with radioactive isotopes].

Nucleoside phosphorylases from E. coli immobilized in polyacrylamide gel were used for production of nucleosides from nitrous bases during the transglucosylase reaction. Phosphorylation of nucleosides resulted in the formation of 5'-nucleotides was performed in the presence of carrot nucleoside phosphotransferase immobilized in polyacrylamide gel. Using 14C-labelled nitrous bases as starting substrates, labelled nucleosides and nucleotides can be obtained with the 75-80% yield that have radioactive purity of 95-99%. The stability of the immobilized enzymes was being studied under the conditions of the reactions using them in the batch and plug flow reactors.