Characterization of yeast strains of the genera candida, Hansenula, Kluyveromyces, Pichia, Rhodotorula, and Saccharomyces by mixed-dye fluorometry.

An analytical method in which we used the selective adsorption of several fluorophores by yeast cells is described. The suitability of using binary mixtures of 1-pyrene butyric acid, 3,6-dimethylamino acridine, 4-acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic acid, and rhodamine B isothiocyanate for the characterization and identification of microorganisms was tested with 98 yeast strains belonging to the genera Candida, Hansenula, Kluyveromyces, Pichia, Rhodotorula, and Saccharomyces. The application of multivariate statistical methods and pattern recognition methods to the allocation of the yeast strains into genus-species-strain structures and to a comparison of fluorescence data sets for differentiation and identification purposes showed the usefulness of the method.