The repertoire of desaturases and elongases reveals fatty acid variations in 56 eukaryotic genomes

J Lipid Res. 2008 Jan;49(1):183-91. doi: 10.1194/jlr.M700377-JLR200. Epub 2007 Oct 7.


The repertoire of biosynthetic enzymes found in an organism is an important clue for elucidating the chemical structural variations of various compounds. In the case of fatty acids, it is essential to examine key enzymes that are desaturases and elongases, whose combination determine the range of fatty acid structures. We systematically investigated 56 eukaryotic genomes to obtain 275 desaturase and 265 elongase homologs. Phylogenetic and motif analysis indicated that the desaturases consisted of four functionally distinct subfamilies and the elongases consisted of two subfamilies. From the combination of the subfamilies, we then predicted the ability to synthesize six types of fatty acids. Consequently, we found that the ranges of synthesizable fatty acids were often different even between closely related organisms. The reason is that, as well as diverging into subfamilies, the enzymes have functionally diverged within the individual subfamilies. Finally, we discuss how the adaptation to individual environments and the ability to synthesize specific metabolites provides some explanation for the diversity of enzyme functions. This study provides an example of a potent strategy to bridge the gap from genomic knowledge to chemical knowledge.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetyltransferases / chemistry*
  • Acetyltransferases / classification
  • Acetyltransferases / genetics
  • Acetyltransferases / metabolism
  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Evolution, Molecular
  • Fatty Acid Desaturases / chemistry*
  • Fatty Acid Desaturases / classification
  • Fatty Acid Desaturases / genetics
  • Fatty Acid Desaturases / metabolism
  • Fatty Acid Elongases
  • Fatty Acids, Unsaturated / biosynthesis*
  • Fatty Acids, Unsaturated / chemistry
  • Fungi / enzymology
  • Genome
  • Humans
  • Molecular Sequence Data
  • Phylogeny
  • Plants / enzymology


  • Fatty Acids, Unsaturated
  • Fatty Acid Desaturases
  • Acetyltransferases
  • Fatty Acid Elongases