TITLE:
Molecular and Kinetic Characterization of the Fermentative Behavior of Saccharomyces cerevisiae Strains Isolated from North Patagonia
AUTHORS:
Adriana Beatriz Simes, Ramona del Carmen Maturano, Valentín Tassile, Adriana Catalina Caballero, Silvana María del Mónaco
KEYWORDS:
Fermentation, Wine, Saccharomyces cerevisiae, Hexose Transporters
JOURNAL NAME:
Advances in Microbiology,
Vol.6 No.9,
August
19,
2016
ABSTRACT: At present, Argentina does
not count with a production of indigenous yeast strains with suitable technological
and oenological features to be used in the regional winery industry. Isolation and
molecular characterization of these microorganisms and its fermentation attributes
would be relevant to the sustainable development of the activity in the country
and to recognize and preserve the biodiversity of the region. Eight strains isolated
from grapes and musts from the North Patagonian region and genetically identified
as Saccharomyces cerevisiae, were studied
for their fermentation behavior, emphasizing in hexose transport through the plasma
membrane, which is the limiting step of the process. Thus, sugar consumption profiles
were analyzed in different media at laboratory scale, to be subsequently applied
to the fermentation of natural musts. Three of the eight initial strains were selected,
named NNM10, NIF8 and NMN16 according to their fermentation profiles. The expression
of hexose transporters during fermentations revealed interesting differences in
the response of each strain to sugar consumption, where transporters HXT2 and HXT5
showed significant changes in expression in Patagonian strains, which are normally
associated to endurance to culture stress conditions. The results obtained by combining
the characteristics studied, at molecular and physiological level, are extremely
encouraging. Native strain NMN16, showed a high potential for application in local
winemaking. Assays carried out on a pilot scale will determine the feasibility of
applying this strain with promising technological features at industrial scale.