Differentiation of Species Belonging to Saccharomyces Sensu Stricto Using a Loop-Mediated Isothermal Amplification Method

Abstract

Primer sets for a loop-mediated isothermal amplification (LAMP) method were developed to specifically identify four species belonging to Saccharomyces sensu stricto and the amylolytic variant of S. cerevisiae (previously known as S. diastaticus). In the analysis of the chromosomal structures of S. pastorianus, some translocations were found between chromosomes of types “Sc” (originating from S. cerevisiae) and “Lg” (possibly originating from S. bayanus) due to chromosomal replacement or rearrangement. These chromosomal features were used to identify target genes in the differentiation of S. cerevisiae, S. pastorianus, and S. bayanus. Primer sets for S. paradoxus and amylolytic S. cerevisiae were also developed using DNA sequences of the TLC1 and STA1 genes, respectively. The LAMP primer sets developed for the four species of Saccharomyces sensu stricto and the S. cerevisiae variant distinguished the target strains from other Saccharomyces spp. and several other yeast genera. Moreover, this method detected approx. 102−103 CFU of Saccharomyces spp. per mL from a suspension containing distilled water, wine, and beer. The LAMP technique was useful for yeast strain identification in wine and beer production and, therefore, for control of the production process and quality of the final product.