Subcellular Localization of the Methylcitric‐Acid‐Cycle Enzymes in Propionate Metabolism of Yarrowia Zipolytica

Abstract

The subcellular localization of the 4 characteristic enzymes of the methylcitric acid cycle was studied with glucose-grown as well as n-alkane-grown cells of Y. lipolytica. Microsomes and peroxisomes showed no cycle enzyme activities. The 4 cycle enzymes were constitutively lcoalized in mitochondria, with the exception of the dual localization of the 4th enzyme, 2-methylisocitrate lyase, in mitochondria and cytoplasm, where the lyase may function to supply pyruvate (the end-product of the catabolism of the propionate residue) to various reactions.