Breakdown of fatty acids in peroxisomes. Pristanic acid and phytanic acid are both methylated branched fatty acids found in various dietary sources. They are metabolized in peroxisomes and alpha-methyl-CoA-racemase (AMACR) is one of the enzymes required for this. Peroxisomes cannot breakdown these fatty acids completely, but require the mitochrondria to continue once C11-CoA is produced. AMACR deficiency leads to an accumulation of pristanic acid that can be measured in blood.