title: A colour reaction for the differentiation of ascomycetous and hemibasidiomycetous yeasts.
abstract: Seventy yeast strains, representative of twenty-six ascogenous genera, four saprobic hemibasidiomycetous genera and thirteen genera of the Cryptococcales were tested for their reaction with the stabilized aromatic diazonium compound, Diazonium Blue B salt. An aqueous, buffered solution of this compound gave a characteristic red colouration with the colonies of the hemibasidiomycetous species and those Cryptococcales characterized by the hemibasidiomycetous cell-wall type. The characteristic colour reaction was not observed with colonies of either the ascomycetous yeasts or those Cryptococcales characterized by the ascomycetous cell-wall type. The possibly taxonomic use of the colour reaction with Diazonium Blue B salt as an affinitive characteristic is discussed.
mesh_terms: D001203:Ascomycota / Q000145:classification*; D001487:Basidiomycota / Q000145:classification*; D003979:Diazonium Compounds; D008722:Methods; D013045:Species Specificity; D013194:Staining and Labeling
chemical_list: D003979:Diazonium Compounds