Isolation and characterization of a calendic acid producing (8,11)-linoleoyl desaturase.

For the biosynthesis of calendic acid a (8,11)-linoleoyl desaturase activity has been proposed. To isolate this desaturase, PCR-based cloning was used. The open reading frame of the isolated full-length cDNA is a 1131 bp sequence encoding a protein of 377 amino acids. For functional identification the cDNA was expressed in Saccharomyces cerevisiae, and formation of calendic acid was analyzed by RP-HPLC. The expression of the heterologous enzyme resulted in a significant amount of calendic acid presumably esterified within phospholipids. The results presented here identify a gene encoding a new type of (1,4)-acyl lipid desaturase.