CYP4 Isoform Specificity in the ω-Hydroxylation of Phytanic Acid, a Potential Route to Elimination of the Causative Agent of Refsum's Disease

  title={CYP4 Isoform Specificity in the $\omega$-Hydroxylation of Phytanic Acid, a Potential Route to Elimination of the Causative Agent of Refsum's Disease},
  author={Fengyun Xu and Valerie Y. Ng and Deanna L Kroetz and Paul R. Ortiz de Montellano},
  journal={Journal of Pharmacology and Experimental Therapeutics},
  pages={835 - 839}
The saturated C20 isoprenoid phytanic acid is physiologically derived from phytol released in the degradation of chlorophyll. The presence of a C-3 methyl group in this substrate blocks normal β-oxidation, so phytanic acid degradation primarily occurs by initial peroxisomal α-oxidation to shift the register of the methyl group. However, individuals with Refsum's disease are genetically deficient in the required phytanoyl-CoA α-hydroxylase and suffer from neurological pathologies caused by the… 

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