Effect of magnesium ions on the inhibition of S-adenosylmethionine decarboxylase from Escherichia coli by [2-(amino-oxy)ethyl](5′-deoxyadenosin-5′-yl)(methyl)sulphonium

[摘要]

[2-(Amino-oxy)ethyl](5′-deoxyadenosin-5′-yl)(methyl)sulphonium+ ++, the amino-oxy analogue of decarboxylated S-adenosylmethionine, is a potent irreversible inhibitor of Escherichia coli S-adenosylmethionine decarboxylase [Khomutov, Zavalova, Syrku, Artamonova & Khomutov (1983) Bioorg. Khim. 9, 130-131; Artamonova, Zavalova, Khomutov & Khomutov (1986) Bioorg. Khim. 12, 206-212]. We have shown that Mg2+ ions are required for the irreversible inhibition of the decarboxylase, and that S-adenosylmethionine protects against this inhibition.