Metabolism of methanol in plant cells.: Carbon-13 nuclear magnetic resonance studies

Using C-13-NMR, we demonstrate that [C-13]methanol readily entered sycamore (Acer pseudoplatanus L.) cells to be slowly metabelited to [3-C-13] serine, [(CH3)-C-13]methionine, and [(CH3)-C-13]phosphatidylcholine. We conclude that the assimilation of [C-13]methanol occurs through the formation of (13)CH(3)H(4)Pte-glutamate (Glu)(n) and S-adenosyl-methionine, because feeding plant cells with [3-(CH3)-C-13]serine, the direct precursor of (13)CH(2)H(4)Pte-Glu(n), can perfectly mimic [(CH3)-C-13]methanol for folate-mediated single-carbon metabolism, On the other hand, the metabolism of [C-13]methanol in plant cells revealed assimilation of label into a new cellular product that was identified as [(CH3)-C-13]methyl-beta-D-glucopyranoside. The de novo synthesis of methyl-beta-D-glucopyranoside induced by methanol did not require the formation of (13)CH(3)H(4)Pte-Glu(n) and was very likely catalyzed by a "transglycosylation" process.