Desaturation of alpha-linoleoyl-CoA to Stearidonoyl-CoA Alpha-linoloyl-CoA is converted to Stearidonoyl-CoA (SDA, 6,9,12,15-18:3(n-3)) by delta-6-destaurase (fatty acid desaturase-2, FADS2). FADS2 uses the cytochrome b5 system to add a double bond at position 6. This is the rate limiting step in alpha-linolenic acid (ALA) metabolism (Horrobin 1993). Authored: Garapati, P V, 2012-01-11 EC Number: 1.14.19.3 Edited: Garapati, P V, 2012-01-11 Pubmed11988075 Pubmed12562861 Pubmed12713571 Pubmed1346092 Pubmed19056654 Pubmed8386433 Reactome Database ID Release 432046084 Reactome, http://www.reactome.org ReactomeREACT_121240 has a Stoichiometric coefficient of 2