methylation of arsenate by a marine alga Polyphysa peniculus in the presence of L-methionine-methyl-D3

The biological methylation of arsenic was considered, with particular reference to the effect of adding L-methionine-methyl-d3 and arsenate to artificial sea water containing the marine alga Polyphysa peniculus. The arsenic metabolites excreted by the algae in the medium were identified using hydride generation-gas chromatography-mass spectrometry. This technique provided proof that the CD3 label was incorporated intact in a dimethylarsenic compound produced by the algae. The study gave evidence that a sulphonium compound such as S-adenosylmethionine was involved in the biological methylation process. A mechanism for the process is proposed. There are 39 references.