Physiology and industrial potential of new Saccharomyces cerevisiae strains isolated from the Brazilian biodiversity

Abstract

In spite of being the most widely utilized organism in the biotech industry and also the best studied eukaryote, the yeast Saccharomyces cerevisiae does not have its natural habitat well characterized. Indigenous strains of this species will be isolated from Atlantic Forest ecosystems by the group of Dr. Carlos Rosa, from the Federal University of Minas Gerais, who will also perform a phylogenetic analysis of these strains. Depending on these results and on some simple fermentation trials, some strains will be chosen to be employed in our project. A detailed and quantitative physiological characterization of these strains will be performed, with the objective of comparing them to well described laboratorial and industrial S. cerevisiae strains. For this purpose, the strains will be cultivated both under full aerobiosis and under complete anaerobiosis, during exponential unlimited growth and also during the steady-state of chemostats operated at a 0.1 1/h dilution rate, always using defined media. Finally, the newly isolated strains will have their industrial potential evaluated, which will be carried out using industrial media (sugar cane juice and/or molasses), under conditions that mimic the industrial processes. It is expected that this project will lead to the identification of yeast strains with physiological properties that are different from the strains currently in use and also strains with high industrial potential. The new strains might also be an interesting source for new genes of biotechnological relevance. (AU)