TAXONOMIC STUDIES ON DEBARYOMYCES HANSENII (ZOPF) LODDER ET KREGER-VAN RIJ AND RELATED SPECIES.

II. PRACTICAL DISCRIMINATION AND NOMENCLATURE

Abstract

Comparative taxonomic studies were carried out on strains of groups I, II and III, and subgroups Ia and Ib of Debaryomyces hansenii and related species which were found in the preceding paper on the basis of chemotaxonomic investigations, for the practical discrimination and clarification of nomenclature. These groups and subgroups could be discriminated from one another by maximum growth temperature, assimilability of propylene glycol, and electrophoretic patterns of glucose-6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49) and malate dehydrogenase (MDH, EC 1.1.1.37), in addition to the criteria reported in the preceding paper.
Strains of group III (Candida saitoana nov. nom.) could be easily discriminated from strains of other groups by their ability to assimilate propylene glycol and electrophoretic relative mobilities of G6PDH and MDH, in addition to their characteristic patterns of PMR spectra of mannans and cell surface antigens. Strains of subgroup Ia (Debaryomyces hansenii var. hansenii-Candida famata var. famata) could be discriminated by their low maximum growth temperature and the lack of G6PDH activity. Discrimination of strains of subgroup Ib (Debaryomyces hansenii var. fabryi nov. comb.-Candida famata var. flareri nov. comb.) from those of group II (Debaryomyces nepalensis-Candida naganishii nov. sp.) is not so easy in the present study. At present, electrophoretic comparison of MDH is the most convenient method for the separation of group II and subgroup Ib from each other because the differences found in the patterns of PMR spectra of mannans and cell surface antigens are not so clear-cut in several strains.