Oxygenation of polyunsaturated long chain fatty acids by recombinant CYP4F8 and CYP4F12 and catalytic importance of Tyr-125 and Gly-328 of CYP4F8

Arch Biochem Biophys. 2005 Sep 15;441(2):174-81. doi: 10.1016/j.abb.2005.07.003.


Recombinant CYP4F8 and CYP4F12 metabolize prostaglandin H2 (PGH2) analogs by omega2- and omega3-hydroxylation and arachidonic acid (20:4n-6) by omega3-hydroxylation. CYP4F8 was found to catalyze epoxidation of docosahexaenoic acid (22:6n-3) and docosapentaenoic acid (22:5n-3) and omega3-hydroxylation of 22:5n-6. CYP4F12 oxidized 22:6n-3 and 22:5n-3 in the same way, but 22:5n-6 was a poor substrate. The products were identified by liquid chromatography-mass spectrometry. The missense mutation 374A>T of CYP4F8 (Tyr125Phe in substrate recognition site-1 (SRS-1)) occurs in low frequency. This variant oxidized two PGH2 analogs, U-51605 and U-44069, in analogy with CYP4F8, but 20:4n-6 and 22:5n-6 were not oxidized. CYP4F enzymes with omega-hydroxylase activity contain a heme-binding Glu residue, whereas CYP4F8 (and CYP4F12) with omega2- and omega 3-hydroxylase activities has a Gly residue in this position of SRS-4. The mutant CYP4F8 Gly328Glu oxidized U-51605 and U-44069 as recombinant CYP4F8, but the hydroxylation of arachidonic acid was shifted from C-18 to C-19. Single amino acid substitutions in SRS-1 and SRS-4 of CYP4F8 may thus influence oxygenation of certain substrates. We conclude that CYP4F8 and CYP4F12 catalyze epoxidation of 22:6n-3 and 22:5n-3, and CYP4F8 omega3-hydroxylation of 22:5n-6.

Publication types

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

MeSH terms

  • Amino Acid Substitution
  • Aryl Hydrocarbon Hydroxylases / chemistry*
  • Aryl Hydrocarbon Hydroxylases / genetics
  • Binding Sites
  • Catalysis
  • Enzyme Activation
  • Fatty Acids, Unsaturated / chemistry*
  • Fatty Acids, Unsaturated / genetics
  • Glycine / chemistry*
  • Glycine / genetics
  • Mixed Function Oxygenases / chemistry*
  • Mixed Function Oxygenases / genetics
  • Molecular Weight
  • Mutagenesis, Site-Directed
  • Oxidation-Reduction
  • Oxygen / chemistry*
  • Protein Binding
  • Protein Engineering / methods
  • Recombinant Proteins / chemistry*
  • Structure-Activity Relationship
  • Tyrosine / chemistry*
  • Tyrosine / genetics


  • Fatty Acids, Unsaturated
  • Recombinant Proteins
  • Tyrosine
  • Mixed Function Oxygenases
  • Aryl Hydrocarbon Hydroxylases
  • CYP4F12 protein, human
  • CYP4F8 protein, human
  • Oxygen
  • Glycine