Diversity of oligopeptide transport in industrial yeasts

Academic partners: INRA, Montpellier, France; UMINHO, Braga, Portugal
Industry Partner : Pernod-Ricard, France

In winemaking fermentation nitrogen is a key nutrient, affecting both fermentation kinetics and the formation of wine aroma. Grape juice is mainly composed of ammonium and amino acids and are utilized as main nitrogen source by yeast. Oligopeptides represent a substantial nitrogen resource for microorganisms in must as well as in different environments. Various families, including the recently identified Fot transporters can coexist in microorganisms but there was a lack of knowledge in oligopeptides transport as well as the transport regulation. This project will identified and characterized oligopeptide transporters in Saccharomyces and non-conventional yeast commonly found in food ecosystems and their impact on yeast fermentative performances. Genomic analysis, RT-PCR, phenotyping microarray and fluorescence-based competitive uptake (F-CUp) assay as well as 14C analysis will be performed to characterize the diversity of oligopeptide transporters and specificity of some of them. The impact of these transporters on fermentation performance, nitrogen consumption and flavour production will be investigated using dedicated robotic and analytic platforms and will be assessed at pilot scale under industry conditions.