First evidence and characterization of an uncoupling protein in fungi kingdom:: CpUCP of Candida parapsilosis

An uncoupling protein (UCP) was identified in mitochondria from Candida parapsilosis (CpUCP), a nonfermentative parasitic yeast, CpUCP Nas immunodetected using polyclonal antibodies raised against plant UCP. Activity of CpUCP, investigated in mitochondria depleted of free fatty acids, was stimulated by Linoleic acid (LA) and inhibited by GTP, Activity of CpUCP enhanced stale 4 respiration by decreasing Delta Psi and lowered the ADP/O ratio. Thus, it was able to divert energy from oxidative phosphorylation. The voltage dependence of electron flux indicated that LA had a pure protonophoretic effect. The discovery of CpUCP proves that UCP-like proteins occur in the four eukaryotic kingdoms: animals, plants, fungi and protists. (C) 2000 Federation of European Biochemical Societies.