Quantitative trait loci mapping of traits related to robustness in industrial yeast Pedra-2 (Saccharomyces cerevisiae)

Abstract

The recognition about environmental consequences arising from use of fossil fuels demand a significantly increase in renewable fuels production,being the bioethanol considered one of the main alternatives. In this context, industrial yeasts have attracted the attention of several research groups and biotechnology companies, because they are considered excellent backgrounds to development of new products. Among the industrial yeasts there is the strain Pedra-2 (PE-2), widely used in Brazilian ethanol production, due its high productivity in industrial environment and ability to tolerate oxidative stress and temperature typically found in the industry. Although the genomic analysis of PE-2 strain has shown the presence of stress-related genes, the genetic basis of their strength are not clearly understood, so a detailed study of QTLs for tolerance to oxidative stress and temperature will contribute significantly to understanding of these mechanisms and consequently for continued development of more productive strains. A large number of derivatives segregant strain from PE-2 (or hybrid PE2 x S288c) will be obtained by flow cytometry using the high-throughput tetrad analysis method. All segregating will be assessed under the stress conditions using standard procedure for high-throughput screening. The segregating identified as tolerant will be sequenced and the QTL will be mapped by bioinformatics and statistics analysis. QTLs potentially related to robustness will be validated using the reciprocal hemizigosidade method.