Metahyphopichia laotica gen. nov., sp. nov., a polymorphic yeast related to Hyphopichia

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Evidence of Natural Hybridization in Brazilian Wild Lineages of Saccharomyces cerevisiae

This work was supported by Fundacao para a Ciencia e a Tecnologia, Portugal, grants PTDC/BIA-EVF/118618/2010 (J.P.S., P.A., P.G.), PTDC/AGR-ALI/118590/2010 (J.P.S., P.A., P.G., R.B.), UID/Multi/04378/2013 (J.P.S., P.G.), and SFRH/BD/77390/2011 (P.A.), by Conselho Nacional de Desenvolvimento Cientifico e Tecnologico-CNPq (CAR, process numbers 560715/2010-2 and 457499/2014-1, PBM process number 457443/2012-0) and Fundacao de Amparo a Pesquisa de Minas Gerais FAPEMIG and VALE S.A (CAR, process number RCP-00094-10). Work of C.R.L. on this project was supported by a NSERC Discovery grant. C.R.L. holds the Canada Research Chair in Evolutionary Cell and Systems Biology. The authors thank Dr. Siu Mui Tsai, Universidade de Sao Paulo, Brazil, for making available strain UFMG-CM-Y640.The natural biology of Saccharomyces cerevisiae, the best known unicellular model eukaryote, remains poorly documented and understood although recent progress has started to change this situation. Studies carried out recently in the Northern Hemisphere revealed the existence of wild populations associated with oak trees in North America, Asia, and in the Mediterranean region. However, in spite of these advances, the global distribution of natural populations of S. cerevisiae, especially in regions were oaks and other members of the Fagaceae are absent, is not well understood. Here we investigate the occurrence of S. cerevisiae in Brazil, atropical region where oaks and other Fagaceae are absent. We report a candidate natural habitat of S. cerevisiae in South America and, using whole-genome data, we uncover new lineages that appear to have as closest relatives the wild populations found in North America and Japan. A population structure analysis revealed the penetration of the wine genotype into the wild Brazilian population, a first observation of the impact of domesticated microbe lineages on the genetic structure of wild populations. Unexpectedly, the Brazilian population shows conspicuous evidence of hybridization with an American population of Saccharomyces paradoxus. Introgressions from S. paradoxus were significantly enriched in genes encoding secondary active transmembrane transporters. We hypothesize that hybridization in tropical wild lineages may have facilitated the habitat transition accompanying the colonization of the tropical ecosystem.publishersversionpublishe