AFLP analysis of type strains and laboratory and industrial strains of Saccharomyces sensu stricto and its application to phenetic clustering.

Using nine primer pairs, amplified fragment length polymorphism (AFLP) analysis was conducted to characterize industrial, laboratory and type strains of Saccharomyces sensu stricto. S. cerevisiae, S. bayanus, S. carlsbergensis and S. paradoxus had species-specific AFLP profiles, with some variations among the strains. Nineteen wine, ale, bakery, whisky and laboratory strains of S. cerevisiae were differentiated by two primer pairs, while out of 19 strains of sake yeast, two groups consisting of two and eight strains were not differentiated using nine primer pairs. A phenogram of 41 strains of S. cerevisiae, two strains of S. bayanus, the type strain of S. pastorianus, three strains of S. carlsbergensis, one hybrid strain of S. cerevisiae and S. bayanus and the type strain of S. paradoxus was obtained by the unweighted pair group method, using arithmetic averages (UPGMA) based on the percentage of shared AFLP fragments of each sample pair. This phenogram demonstrated clear separations of S. cerevisiae, S. bayanus, S. carlsbergensis and S. paradoxus. However, S. pastorianus ATCC 12752(T) showed the highest percentages of shared fragments with the strains of S. bayanus, and formed a cluster with them. Except for the type strain of S. pastorianus, the percentages of shared fragments showed a similar tendency with reported data of DNA relatedness. The cluster of S. cerevisiae separated into three subclusters: one consisting of sake and shochu strains and a whisky strain; another consisting of bakery, wine, ale and whisky strains; and a third consisting of laboratory strains.