Molecular and kinetic characterization of the fermentative behavior of Saccharomyces cerevisiae strains isolated from North Patagonia.

ADRIANA BEATRIZ SIMES; RAMONA DEL CARMEN MATURANO; VALENTIN TASSILE; ADRIANA CATALINA CABALLERO; SILVANA MARÍA DEL MÓNACO

Advances in Microbiology

Scientific Research Publishing

Año: 2016 vol. 6 p. 733 - 744

2165-3402

At present, Argentina does not count with a production of indigenous yeast strains with suitabletechnological and oenological features to be used in the regional winery industry. Isolation andmolecular characterization of these microorganisms and its fermentation attributes would be relevantto the sustainable development of the activity in the country and to recognize and preservethe biodiversity of the region. Eight strains isolated from grapes and musts from the North Patagonianregion and genetically identified as Saccharomyces cerevisiae, were studied for their fermentationbehavior, emphasizing in hexose transport through the plasma membrane, which is thelimiting step of the process. Thus, sugar consumption profiles were analyzed in different media atlaboratory scale, to be subsequently applied to the fermentation of natural musts. Three of theeight initial strains were selected, named ÑNM10, ÑIF8 and ÑMN16 according to their fermentationprofiles. The expression of hexose transporters during fermentations revealed interestingdifferences in the response of each strain to sugar consumption, where transporters HXT2 andHXT5 showed significant changes in expression in Patagonian strains, which are normally associatedto endurance to culture stress conditions. The results obtained by combining the characteristicsstudied, at molecular and physiological level, are extremely encouraging. Native strainÑMN16, showed a high potential for application in local winemaking. Assays carried out on a pilotscale will determine the feasibility of applying this strain with promising technological features atindustrial scale.