Phylogenetic analysis of the Saccharomyces cerevisiae group based on polymorphisms of rDNA spacer sequences

Abstract

Phylogenetic analysis of the Saccharomyces cerevisiae group based on polymorphisms of rDNA spacer sequencesRobert M on t roc her, M a r i e-C h r ist i ne Verner, JerBme B r io I ay,2 Christian Gautier2 and Roland Marrneissel The phylogenetic relationships between species of yeasts assigned to the Saccharomyces sensu stricto group, which includes Saccharomyces cerevisiae and Saccharomyces bayanus, were studied together with Saccharomyces pastorianus and Saccharomyces paradoxus. The ex per i mental approaches used were RFLP analysis of the PCR-amplified rDNA internal transcribed spacer (ITS) and intergenic spacer, and total ITS sequence analysis. Both RFLP and sequence analyses gave fairly similar results. The gene trees generated with either of the two data sets showed the distribution of the yeasts into two major, wellseparated, phylogenetic clusters called ' cerevisiae ' and 'bayanus '. The 'cerevisiae' cluster included the 5. cerewisiae type strain, together with most of the species (16 out of 23), whereas the 'bayanus' cluster included the remaining seven type strains. Therefore, analysis of rDNA sequences confirmed 5. cerewisiae and 5. bayanus as two well-defined taxa. However, 5. pastorianus and S. paradoxus, the two other usually accepted taxa of the nowdefined Saccharomyces sensu stricto complex, could not be clearly separated from 5. bayanus and 5. cerevisiae, respectively. However, in both PCR-RFLP and ITS sequence analyses, S. paradoxus had the outermost position in the cerevisiae cluster. PCR-RFLP analysis of the ribosomal spacer sequences was also carried out on 26 Saccharomyces strains isolated in various wine-growing regions of France in an attempt to clarify their positions in the Saccharomyces phylogenetic tree. Compared to the diversity of the Saccharomyces type strains, less genetic diversity was detected among these yeasts and several of them exhibited identical RFLP patterns. Most of the wine yeast strains (16 out of 26) were closely related to each other and were found within the 'cerevisiae' cluster. The remaining 10 wine yeast strains branched within the bayanus cluster. PCR-RFLP analysis of ribosomal spacer sequences thus appears to be a useful and appropriate method for the correct characterization of Saccharomyces yeast strains used in food processing.

Differentiation of Brewing and Related Yeasts Based on PCR Amplification and Restriction Fragment Length Polymorphism of Ribosomal DNA

“…This is in accordance with the rather isolated position of Sacch. paradoxus when compared with the other members of the "cerevisiae" cluster based on PCR-RFLP and ITS sequence analyses as reported by Montrocher et al 8 In addition, the Saccharomyces sensu stricto group could easily be differentiated from the Saccharomyces sensu lato group when comparing band patterns after Sau 3A1 digestion (Fig. 4, Table IV).…”

“…In recent times, there have been a number of reports describing the application of molecular genetic tools for the differentiation and characterisation of yeasts used in industrial fermentation 2,3,4,7,8,9,11 . Data from these studies show that RFLP patterns allow recognition of individual species as well as individual strains within a species.…”

Evidence for S. cerevisiae Fermentation in Ancient Wine

“…The 840-bp fragment corresponds in size to the region encompassing S. cerevisiae chromosome 12 coordinates 455966-455123 comprising 394 bp of ITS1, 158 bp of 5.8S rDNA, and 288 bp of ITS2. To confirm the Saccharomyces origin of the 840-bp product, we designed new primers ITS5 and ITS6, internal to the 840-bp S. cerevisiae ITS1-5.8S rDNA-ITS2 sequence, which would specifically amplify sequences belonging to the genus Saccharomyces (Montrocher et al 1998). Amplifications of the extracted DNA with the primer pair ITS1-ITS6 produced a band of 320 bp, amplification with ITS5-ITS4 produced a band of 650 bp, and amplification with ITS5-ITS6 produced a band of 130 bp.…”

Molecular genetic study of introgression between Saccharomyces bayanus and S. cerevisiae

“…Based on rDNA sequences and molecular karyotyping, the species was divided into two subgroups, 'bayanus' and 'uvarum' (Nguyen and Gaillardin, 1997;Gouliamova and Hennebert, 1998;Montrocher et al, 1998;Rainieri et al, 1999;Naumov et al, 2000a), which were later identified by genetic hybridization analysis as two varieties (Naumov, 2000 The growing interest in studying S. bayanus species is connected not only with its possible role as a contributor to the S. carlsbergensis genome but also with its significance as a new gene pool for the cultured Saccharomyces yeasts. The specific ecological niche of S. bayanus var.…”