ABSTRACT
The POX 18 gene encodes a small oleate-inducible peroxisomal protein from Candida tropicalis. The genes POX2 and POX4, encoding the subunits of peroxisomal acyl-CoA oxidase of C. tropicalis, were introduced on a multicopy plasmid into the related yeast Candida maltosa. Peroxisomes of yeasts grown on alkanes play an essential role in the catabolism of fatty acids derived from alkanes. In the methylotrophic yeast Hansenula polymorpha, peroxisomes are induced by growth on methanol. Glucose-grown cells of methanol-utilizing yeasts contain few peroxisomes. Transfer to media containing various compounds known to induce peroxisome proliferation in other yeasts was ineffective. The transformed yeast cells were grown on oleic acid under conditions that induce peroxisome proliferation. Immunogold labeling indicated that luciferase was located in peroxisomes. The presumptive ancestor of peroxisomes might have been a prokaryote endowed with many metabolic capacities. Peroxisomal disorders have been described in man.
