GENOTYPIC IDENTIFICATION OF SACCHAROMYCES SPECIES USING RANDOM AMPLIFIED POLYMORPHIC DNA ANALYSIS

According to different molecular approaches the genus Saccharomyces was divided recently into 10 genotypically distinct species (S. bayanus, S. castellii, S. cerevisiae, S. dairensis, S. exiguus, S. kluyveri, S. paradoxus, S. pastorianus, S. servazzii, S. unisporus). This was corroborated by Random Amplified Polymorphic DNA - Polymerase Chain Reaction (RAPD-PCR) analysis in the present paper. Thirtytwo strains including the type strains of 20 Saccharomyces species defined originally by phenotypic characteristics (e.g. S. chevalieri, S. diastaticus, S. ellipsoideus) clustered with the pattern of S. cerevisiae, fourteen (e.g. type strains of S. globosus, S. heterogenicus, S. inustiatus) with the pattern of S. bayanus, six including the type strains of S. carlsbergensis and S. monacensis with the pattern of S. pastorianus and two with the pattern of S. paradoxus. Two further strains isolated newly were identified to belong to S. paradoxus. In comparison with nuclear DNA/DNA hybridization or electrophoretic karyotyping, RAPD-PCR anaylsis turned out to be a simple and reliable method to separate Saccharomyces species at the genotypic level. In contrast to phenotypic characters genotypic identification using RAPD-PCR analysis guarantees species specificity if type strains are included in the investigation. The ten Saccharomyces species arising from RAPD-PCR analysis are differentiated from each other to the maximal extent with exception of the relationship between S. bayanus and S. pastorianus. In this case, the estimated similarity value of 45% is significantly higher than the background noise (0-20%), but less than the values within species (83 to 100%).