Methylantimony compound formation in the medium of Scopulariopsis brevicaulis cultures: 13CD3-L-methionine as a source of the methyl group

The filamentous fungus Scopulariopsis brevicaulis produces nonvolatile methylantimony compounds (found in the medium) when grown in antimony(III)-rich medium. To investigate the methyl source, 13CD3-labelled L-methionine was added to the growth medium. After one month sodium borohydride reduction of media samples produced dimethylstibine and trimethylstibine. The methylstibines were separated on a packed GC column and obtained as gaseous fractions. Analysis of the methylstibines, in the gaseous fractions, by CGC–MS (ion-trap) established 13CD3 incorporation in both the trimethyl-and dimethyl-antimony compounds. Copyright © 1999 John Wiley & Sons, Ltd.