Alternative cyanide- and antimycin A-insensitive respiratory system in Sporobolomyces red yeasts.

Abstract

Sporobolomyces ruberrimus is insensitive to antimycin A which is a respiratory inhibitor of the cytochrome system, as cyanide is. When this red yeast was cultured in the presence of antimycin A, the growth curve showed the same pattern as that of the normal culture in the absence of it, but the growth mass was only about 70% of that of the normal culture. The antimycin A-insensitive and cyanide-insensitive respiration of Sp. ruberrimus was inhibited by pyrocatechol and salicylhydroxamic acid. Sporobolomyces red yeasts have two characteristic terminal oxidase systems; one is a cytochrome oxidase system and the other is a cyanide- and antimycin A-insensitive oxidase system. The proportions of the two respiratory systems differed among the species and strains of Sporobolomyces red yeasts examined.