Enhancing yeast sugar transport capacity under stress conditions

Academic partners: UMinho, Braga, Portugal; UCC, Cork, Ireland
Industry Partner: Biotrend, Portugal

Sugar transport rate is usually the parameter limiting yeast growth and fermentation, the capacity of sugar transporters being, as such, of enormous importance in biotechnological applications. A very limited number of sugar transporters are characterized in the emerging industrially relevant yeasts Kluyveromyces marxianus and Zygosaccharomyces bailii, and none under stress conditions. This project aims to identify in the genomes of K. marxianus and Z. bailii putative sugar transporters (C5 and C6) and establish their substrate specificity and transport capacity under stress conditions relevant for industrial production processes exploring inexpensive commercial substrates. Functional annotation using bioinformatics tools, RNASeq, transport studies and functional genomics will be used. New strains predicted to have enhanced sugar transport activity will be constructed and evaluated under industrial conditions to determine whether they display the enhanced substrate flexibility envisioned and to understand the parameters that led to successful or unsuccessful performance of particular transporters.