ABSTRACT
Yeast strains utilizing uric acid, adenine, monoamines or diamines as sole source of carbon and energy were isolated from several soil samples by the enrichment culture method. The most common species was Trichosporon cutaneum. Strains of Candida catenulata, C. famata, C. parapsilosis, C. rugosa, Cryptococcus laurentii, Stephanoascus ciferrii and Tr. adeninovorans were also isolated. All strains utilizing uric acid as sole carbon source utilized some primary n-alkyl-l-amines, hydroxyamines or diamines as well. The ascomycetous yeast strains showing these characteristics all belonged to species known to assimilate hydrocarbons. Type strains of hydrocarbon-positive yeast species which were not found in the enrichment cultures generally assimilated putrescine, some type strains also butylamine or pentylamine, but none assimilated uric acid. Methanol-positive species were not isolated. Type strains of methanol-positive and of hydrocarbon-negative species did not assimilate uric acid, butylamine or putrescine. Assimilation of putrescine as sole source of carbon and energy may be a valuable diagnostic criterion in yeast taxonomy.
