Evaluating the strain effect in a model consortium of the wine yeast community
Résumé
In recent years, many synthetic communities have been designed to help understanding ecological drivers of microbial interactions. Fermented food microbial communities, such as the wine yeast community, offer a great opportunity to develop model consortia due to their reduced initial diversity compared to other environmental microbial communities. While the species included in such consortia are generally well discussed, little attention has been paid to the strain choice when constructing synthetic consortia. Here, we sought to investigate the effect of yeast strains on the fermentation of nine randomly generated consortia. Each consortium was composed of the same set of seven species representing the most commonly isolated from winemaking environments (Saccharomyces cerevisiae, Hanseniaspora uvarum, Metschnikowia pulcherrima, Pichia kudriavzevii, Starmerella bacillaris, Lachancea thermotolerans, and Torulaspora delbrueckii) but with different strain compositions (3 strains per non-Saccharomyces species). To compare the performance of the nine consortia, we assessed the fermentation kinetics, the population dynamics and the final concentrations of central carbon metabolites. Despite the initial intraspecific phenotype variability of the strains, our results suggest that strains had limited impact on the fermentation kinetics and invasion by S. cerevisiae when included in consortia. Indeed, we observed very few specific associations between a specific strain and variations of phenotypic traits in consortia. Our findings will be of great interest for microbial ecology research and conception of optimized microbial consortia.