The lipids in photoautotrophic and heterotrophic cell suspension cultures of Chenopodium rubrum

Resembling the lipids in the leaves and other green organs of intact plants, the lipids in photoautotrophic cell cultures of Chenopodium rubrum were found to contain high proportions of monogalactosyldiacylglycerols and digalactosyldiacylglycerols, as well as fair amounts of sulfoquinovosyldiacylglycerols and diacylglycerophosphoglycerols. Conversely, the heterotrophic cell cultures, from which the photoautotrophic cultures had been derived, contained only traces of these compounds. The heterotrophic cultures were rich in sterols, sterol esters, sterol glycosides, and esterified sterol glycosides. The lipids of photoautotrophic cell cultures contained higher proportions of constituent linolenic acid, but lower concentrations of linoleic acid than those of heterotrophic cultures. In the photoautotrophic cultures, as in green leaves, linolenic acid was predominantly estrified in monogalactosyldiacylglycerols and digalactosyldiacylglycerols. This investigation shows that it is possible to select strains of cell cultures, which are capable of grosing photoautotrophically, with the aim of activating the biosynthesis of specific metabolites.