Evidence for multiple interspecific hybridization in Saccharomyces sensu stricto species.
de Barros Lopes M, Bellon JR, Shirley NJ, Ganter PF
FEMS Yeast Research (2002)
Category: yeast taxonomy ¤ Added: Mar 25, 2002 ¤ Rating: ◊
Fluorescent amplified fragment length polymorphism analysis demonstrates a high level of gene exchange between Saccharomyces sensu stricto species, with some strains having undergone multiple interspecific hybridization events with subsequent changes in genome complexity. Two lager strains were shown to be hybrids between Saccharomyces cerevisiae and the alloploid species Saccharomyces pastorianus. The genome structure of CBS 380T, the type strain of Saccharomyces bayanus, is also consistent with S. pastorianus gene transfer. The results indicate that the cider yeast, CID1, possesses nuclear DNA from three separate species. Mating experiments show that there are no barriers to interspecific conjugation of haploid cells. Furthermore, the allopolyploid strains were able to undergo further hybridizations with other Saccharomyces sensu stricto yeasts. These results demonstrate that introgression between the Saccharomyces sensu stricto species is likely. fl 2002 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.