Convergent adaptation of Saccharomyces uvarum to an antimicrobial preservative in human-driven fermentations

QUEROL A.; MACIAS L; GONZÁLEZ FLORES, M.; ADAM C.; RODRÍGUEZ M.E; BARRIO E.; LOPES C.A.; PEREZ TORRADO R.

Simposio; 34th International Specialised Symposium on Yeast; 2018

Different species can find convergent solutions to evolutionary constraints. There areexamples of genetic convergence due to point mutations, gene duplications or specieshybridizations but gene conversion by chromosomal rearrangements have notpreviously been described. In this work, we describe that two domesticated yeastspecies, Saccharomyces cerevisiae and Saccharomyces uvarum, acquired chromosomalrearrangements to convergently adapt to the presence of sulfite in (wine and cider)fermentation environments. We found new heterologous recombinations in fermentativestrains of S. uvarum at the SSU1 locus, implicated in sulfite resistance, an antimicrobialadditive used in winemaking and cider production. These are parallel events ofpreviously described SSU1 locus recombinations in domesticated strains of S.cerevisiae. In S. uvarum, XVIVII recombination generates an overexpression of SSU1 gene and confers increased resistance to SO32-. This study highlights the relevance ofchromosomal rearrangements as a generator of genetic diversity in yeast adaptationsto human-manipulated environments. Acknowledgments This work has supported by grantsAGL2015-67504-C3-1-R and AGL2015-67504-C3-3-R from the Spanish Government to AQ andEB and grants COOPB20316 from CSIC to AQ.