Molecular Genetic Features of Biological Species of the Genus Saccharomyces

Abstract

Molecular genetic study of Saccharomyces yeasts of different species was carried out using molecular karyotyping and comparative analysis of a number of nuclear and mitochondrial genes. Multigene phylogenetic analysis showed that the recently described species S. jurei was phylogenetically closest to S. mikatae, while S. bayanus and S. arboricola were the most divergent species within the genus Saccharomyces. Comparative analysis of amino acid sequences of the SUC β-fructosidase genes also indicated a close genetic relationship between the species S. jurei and S. mikatae. The biological species S. cerevisiae, S. kudriavzevii, and S. paradoxus possessed collinear karyotypes. Two reciprocal translocations were found in the S. jurei karyotype, one of which was unique (between chromosomes I and XIII), and the second was common with S. mikatae: VI/VII. Reciprocal translocations in the karyotypes of S. arboricola, S. bayanus, and S. cariocanus were species-specific. It was established that only chromosome III carrying the mating type locus MAT was of approximately the same size in all eight species of the genus Saccharomyces. The adaptive role of reciprocal translocations of chromosomes is discussed.