title: [Conditions and characteristics of the early stages of the sexual interaction of Pichia amethionina var. amethionina and Pichia amethionina var. pachycereana yeast cells].
abstract: Pichia amethionina varieties have different sensitivity to the acidity of the medium: P. amethionina var. amethionina has the optimum pH 3 for agglutination and 5 for conjugation; P. amethionina var. pachycereana has the optimum pH 4-6 for agglutination and 6 for conjugation. The optimum temperature for the both organisms is 24 degrees C. Under the optimum conditions, P. amethionina var. amethionina has a 98% agglutination and a 28% conjugation; for P. amethionina var. pachycereana, these values are 83 and 55%, respectively. The agglutination of the two varieties does not depend on the presence of glucose. The conjugation of P. amethionina var. pachycereana does not occur in a medium without glucose while the conjugation of P. amethionina var. amethionina is reduced twofold under these conditions. Inositol, biotin and folic acid produce positive effect on the conjugation of P. amethionina var. pachycereana, but only folic acid favours the conjugation of P. amethionina var. amethionina. No differences have been found between the varieties by staining their cells and zygotes with FITC-ConA.
mesh_terms: D000371:Agglutination / Q000187:drug effects; D001203:Ascomycota / Q000502:physiology*; D002455:Cell Division / Q000187:drug effects; D003470:Culture Media / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D010843:Pichia / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D012098:Reproduction / Q000187:drug effects; D013696:Temperature; D013997:Time Factors
chemical_list: D003470:Culture Media
vernacular_title: Usloviia i osobennosti rannikh étapov polovogo vzaimodeĭstviia kletok drozhzheĭ Pichia amethionina var. amethionina i Pichia amethionina var. pachycereana.