Phylogenetic supernetworks and microarray CGH analysis suggest several origins for S. cerevisiae x S. kudriavzevii hybrids

PERIS D.; ARIAS A.; GONZÁLEZ S.S.; LOPES C.A.; BARRIO E.

Guadalajara

Simposio; 29th International Specialised Symposium on Yeast; 2011

International Commission on Yeasts

In the last years, interspecific hybridization, and also introgression, are increasinglyrecognized as significant events in the adaptive evolution of Saccharomyces yeasts.These mechanisms have been proposed as involved in the origin of novel yeastgenotypes and phenotypes of adaptive value to colonize and predominate in the newfermentative environments created by human manipulation. The particular conditions inwhich hybrids arose are still unknown, as well as the number of possible hybridizationevents that generated the whole set of natural hybrids described in the literature duringthe last years.In this study, we could infer at least seven different hybridization events that originateda set of 26 S. cerevisiae x S. kudriavzevii hybrids isolated from both fermentative andnon-fermentative environments. Two wine/European S. cerevisiae strains and twoEuropean S. kudriavzevii strains were probably involved in the different hybridizationevents according to a phylogenetic supernetwork analysis, used for the first time in thiskind of studies, as well as from previous data on their genome composition, ploidy, etc.The success of this kind of hybrids is explained by their better adaptation to ferment atlower temperatures than the parental S. cerevisiae in areas of the Northern limits ofvine growing. This advantage allowed them to spread in Central Europe with theexpansion of vine growing and winemaking practices occurred during the Middle Agesthat took place as a result of the Cistercian reformation.