Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: September 3, 1998
Publication Date: N/A
Technical Abstract: At present, the family Saccharomycetaceae includes the genera Arxiozyma, Hanseniaspora (anamorph Kloeckera), Kluyveromyces, Pachytichospora, Saccharomyces, Saccharomycodes, Torulaspora, Zygosaccharomyces, and possibly Eremothecium. The economic impact of these genera is enormous. Species assigned to Saccharomyces are central to the baking and fermentation industries, whereas species in the genus Zygosaccharomyces are among the most common of food spoilage organisms. There are currently 63 species assigned to these genera, and on the basis of various molecular comparisons, all appear genetically isolated from one another. Many of the species have similar phenotypic characters, which has lead to their placement in several of the genera. We determined relationships among the species from phylogenetic analysis of nucleotide sequences from 26S rDNA domain D1/D2, 18S rDNA, mitochondrial small subunit rDNA, ITS1/5.8/ITS2 rDNA, and the translation elongation factor (EF-1?) gene. Close species relationships determined from analysis of the five gene sequences were highly concordant. None of the gene trees gave strong support for basal lineages, but each showed that presently accepted genera are not phylogenetically circumscribed. Analysis of the combined sequences provided stronger support for basal lineages and proposed species assignments to the various genera will be presented. In addition, strategies for rapid species identification using molecular comparisons will be discussed.