Prospecting genes of xylose metabolism of yeasts isolated from brazilian plague insects and functional expression in industrial Saccharomyces cerevisiae yeasts strains

Abstract

Commercial instability and the ecologically costly use of petroleum subproducts are the main reasons for the increase of research in biocompounds area. The ethanol production from sugarcane bagasse, second-generation ethanol (2G), is an alternative. The strains used industrially for the production of ethanol in Brazil, however, do not consume the major pentose present in sugarcane bagasse. Despite several attempts to obtain strains that consume these sugars, they still do not have a satisfactory performance with strains obtained to produce ethanol in industrial scale. Genes that will be explored in this work are presented as viable alternatives to solve this obstacle. Through prospecting xylose catabolism gene and transporter genes for efficient expression in industrial strains we expect to obtain a strain with high performance in ethanol production. These genes will be prospected from a collection of consuming xylose yeasts, previously built. Some strains that exhibit high uptake rate of xylose present in the collection and no published genome, will have the genome sequenced to obtain the genes of interest. Finally, the isolated genes will be expressed in industrial strains of Saccharomyces cerevisiae in order to produce 2G ethanol. Additionally, will be made the physiological characterization of some yeasts from collection, through fermentation tests with xylose and hydrolyzate obtained from lignocellulosic biomass, in order to find a robust platform for the production of renewable chemicals, which is of great industrial interest