Genetic determination of Saccharomyces cerevisiae et Saccharomyces bayanus species by PCR/RFLP analysis of the MET2 gene

Several yeast strains of the species S. cerevisiae, S. bayanus and S. paradoxus, first identified by hybridization experiments and DNA/DNA hybridization were characterized by using Polymerase Chain Reaction/Restriction Fragment Length Polymorphism (PCR/RFLP) of the MET2 gene. The concordance between this tool and classical genetic analyses did not reveal any exception for all the strains analysed, so PCR/RFLP of the MET2 gene proves to be a reliable and fast tool for delimiting S. cerevisiae and S. bayanus. OEnological strains race bayanus, chevalieri, capensis gave S. cerevisiae restriction patterns, whereas most of strains race S. uvarum belong to S. bayanus and displayed a specific chromosomal band patterns different from band patterns of S. cerevisiae strains. To avoid confusion in oenological terminology, oenologists should no longer use the name of bayanus to designate industrial or wild S. cerevisiae Gal- strains, and should consider S. bayanus as a distinct species.