Effect of vanadate and pyridoxal phosphate on S-adenosylmethionine.
Vanadate in the presence of pyridoxal phosphate promotes the decarboxylation of S-adenosylmethionine. Pyridoxal has a lower effect; pyridoxine none. The rate of decarboxylation depends on pyridoxal phosphate and vanadate concentration. Vanadate as low as 10(-7) M gives significant decarboxylation. The reaction seems to occur through the formation of a Schiff base. The spectral shift elicited by S-adenosylmethionine on pyridoxal phosphate due to the presence of the sulfonium function is influenced by vanadate. Orthovanadate is a little less effective then metavanadate; vanadyl sulfate is even less efficient, and the effect of Cu2+ at the same concentration is still lower. Bleomycin partially prevents the vanadium effect. In vivo, vanadate promotes a marked increase in chicken liver S-adenosylmethionine and S-adenosylhomocysteine concentration, whereas the polyamine concentration is unaffected.
S
S
Colombatto
M A
MA
Grillo
D000818:Animals; D001761:Bleomycin / Q000494:pharmacology; D002645:Chickens; D003300:Copper / Q000494:pharmacology; D003653:Decarboxylation; D066298:In Vitro Techniques; D008099:Liver / Q000378:metabolism; D008297:Male; D011732:Pyridoxal Phosphate / Q000494:pharmacology*; D012435:S-Adenosylhomocysteine / Q000378:metabolism; D012436:S-Adenosylmethionine / Q000378:metabolism*; D014638:Vanadates; D014639:Vanadium / Q000494:pharmacology*; D017968:Vanadium Compounds
D017968:Vanadium Compounds; D014639:Vanadium; D001761:Bleomycin; D014638:Vanadates; D011732:Pyridoxal Phosphate; C034028:vanadyl sulfate; D003300:Copper; D012436:S-Adenosylmethionine; D012435:S-Adenosylhomocysteine