METABOLIC FORMATION OF NUCLEOSIDE-MODIFIED ANALOGS OF S-ADENOSYLMETHIONINE

Evidence is presented for the metabolism of six different adenosine analogues (formycin, 7-deazaadenosine, 8-azaadenosine, 2-fluoroadenosine, purine ribonucleoside and 3′-deoxyadenosine) to their corresponding S-nucleosidylmethionine derivatives in human erythrocytes and mouse lymphocytes. The identification of these novel metabolites was based upon chromatographic and enzymatic characterization of the unique radioactive substance found in cells incubated with each of these adenosine analogues plus L-[methyl-3H]methionine. The metabolic formation of analogues of S-adenosylmethionine may contribute to the inhibition of cellular methylation reactions caused by various purine analogues. © 1979.