Biodiversity study of wine yeasts belonging to the “terroir” of Montepulciano d'Abruzzo “Colline Teramane” revealed Saccharomyces cerevisiae strains exhibiting atypical and unique 5.8S-ITS restriction patterns

The Montepulciano d'Abruzzo “Colline Teramane” premium wine DOCG is produced in the Teramo province (Abruzzo, Italy). This region has a great tradition in winemaking and the wine is produced by a spontaneous fermentation so it could represent a reservoir of wine natural yeasts with important oenological features. The aim of this study was to characterize the yeast community of this wine grape growing region in order to create a Saccharomyces cerevisiae bank, providing data on oenological properties for potential industrial applications. A total of 430 yeasts were isolated at the end of spontaneous fermentation. PCR-RFLP was applied for the identification at the species level and underlined that 14 strains exhibited unusual and characteristic restriction patterns different from those typical of the species S. cerevisiae. This difference was due to the insertion of base C at a position 138 in the ITS1 region that determined an additional cleavage site for the enzyme HaeIII. This insertion could be associated to the fermentative performance and associated to the relationship existing between yeasts and a viticulture region or 'terroir'.