Allо- And Sympatric Sibling Species of Saccharоmyсes Cerevisiae: Dna-Dna Reassociation

Abstract

Precise DNA-DNA reassociation data were obtained for new biological species S. cariocanus, S. kudriavzevii and S. mikatae, for the first time. The three species showed 25-51 % - of DNA-DNA reassociation with one another and with the known species S. cerevisiae, S. bayanus and S. paradoxus.Only in the combination S. paradoxus × S. cariocanus there was 99 % DNA-DNA homology. Despite high DNA-DNA reassociation value, the two yeasts are genetically isolated: their hybrids are sterile forming non-viable meiotic products (ascospores). Having four reciprocal translocations in its karyotype, S. cariocanus represents species in statu nascendi.