The Incorporation of [14C]Methionine into Chromanols and Quinones by <i>Hevea brasiliensis</i> Latex

Abstract

The incorporation of shikimate into a-tocopherol, y-tocopherol and a-tocopherolquinone in maize shoots has been reported by Whistance, Threlfall & Goodwin (1966). A possible route for the final stages of tocopherol biosynthesis was suggested by Pennock, Hemming & Kerr (1964), involving methylation of 8-tocotrienol to ,-or y-tocotrienol, further methylation to oc-tocotrienol and followed by reduction to a-tocopherol. The latex of Hevea brasiliensis contains substantial amounts of ytocotrienol together with smaller amounts of a-and 8-tocotrienol in both free and esterified forms (Dunphy, Whittle, Pennock & Morton, 1965), and this communication reports on a small incorporation of labelling from [Me-14C]methionine into some chromanols and quinones by the cell-free system of Hevea latex.