A palmitoyl-CoA-specific delta9 fatty acid desaturase from Caenorhabditis elegans

Biochem Biophys Res Commun. 2000 May 27;272(1):263-9. doi: 10.1006/bbrc.2000.2772.


Biosynthesis of polyunsaturated fatty acids in C. elegans is initiated by the introduction of a double bond at the delta9 position of a saturated fatty acid. We identified three C. elegans fatty acid desaturase genes related to the yeast delta9 desaturase OLE1 and the rat stearoyl-CoA desaturase SCD1. Heterologous expression of all three genes rescues the fatty acid auxotrophy of the yeast delta9 desaturase mutant ole1. Examination of the fatty acid composition of the transgenic yeast reveals striking differences in the substrate specificities of these desaturases. Two desaturases, FAT-6 and FAT-7, readily desaturate stearic acid (18:0) and show less activity on palmitic acid (16:0). In contrast, the other desaturase, FAT-5, readily desaturates palmitic acid (16:0), but shows nearly undetectable activity on the common delta9 substrate stearic acid. This is the first report of a palmitoyl-CoA-specific membrane fatty acid desaturase.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Caenorhabditis elegans / enzymology*
  • Caenorhabditis elegans / genetics*
  • Cloning, Molecular
  • DNA Primers / genetics
  • Fatty Acid Desaturases / genetics*
  • Fatty Acid Desaturases / metabolism*
  • Genes, Helminth
  • Molecular Sequence Data
  • Rats
  • Saccharomyces cerevisiae / enzymology
  • Saccharomyces cerevisiae / genetics
  • Sequence Homology, Amino Acid
  • Stearoyl-CoA Desaturase


  • DNA Primers
  • Fatty Acid Desaturases
  • Stearoyl-CoA Desaturase
  • delta-9 fatty acid desaturase
  • palmitoyl-CoA desaturase