Biosynthesis of eicosapentaenoic acid (EPA) in the freshwater eustigmatophyte Monodus subterraneus (Eustigmatophyceae) Academic Article uri icon

abstract

  • In an attempt to elucidate the biosynthesis of the polyunsaturated fatty acid eicosapentaenoic acid (20: 5ω3, EPA), we treated cultures of the eustigmatophyte Monodus subterraneus Peterson with either salicylhydroxamic acid or the herbicide SAN 9785. Labeled linoleic acid was incorporated into the cultures in the presence and absence of the latter inhibitor, and the redistribution of label was followed. Our results suggest that the major biosynthetic pathway leading to EPA involves fatty acids of the ω6 family. In the early stages of the biosynthesis, 18: 1 is predominantly incorporated to the sn‐2 position of phosphatidylcholine, where it is stepwise desaturated by the Δ12 and Δ6 desaturases to 18: 3ω6. The latter is released from the lipid, elongated to 20: 3ω6 and reincorporated to both positions of phosphatidylethanolamine (PE) where it is further desaturated by the Δ5 and …

publication date

  • January 1, 2002