Genomics and phylogeography of the Lager yeast parent: Saccharomyces eubayanus

LIBKIND D. ; EIZAGUIRRE J. ; PERIS D. ; BAKER B. ; WANG B.; LOPES C.A.; RODRÍGUEZ M.E; HITTINGER C.

Recife

Jornada; V Jornadas Sudamericanas de Biología y Biotecnología de Levaduras; 2015

Saccharomyces eubayanus, the non-Saccharomyces cerevisiae parent of the lager-brewing yeasts, known as Saccharomyces pastorianus syn. S. carlsbergensis was originally isolated from Patagonian forests in Argentina. Later, genetically different isolates were obtained from trees in USA and China. As a result several speculations on the geographic origin of the Lager ancestor were generated and controversy existed on whether a single or multiple hybridization events gave rise to the currently industrially used Lager yeasts (Forhberg and Saaz groups). In this work, we summarize the current knowledge on the worldwide distribution and tree association of S. eubayanus, with special emphasis on the patagonian area and Nothofagus forest. Multi-locus typing and genomic data was used to determine the genetic structure of this species in Patagonia, compare with the sister and sympatric species Saccharomyces uvarum and relate with eco-geological factors. The different molecular markers used showed the existence in Patagonia of two major lineages that share habitat only above latitude 42° and possess substantial internal genetic divergence. Moreover, based on new high-quality genome data for the type strain CRUB 1568T and through comparative analyses with the genome of multiple Lager yeasts we provide insights on the evolutionary history of these domesticated allopolyploid hybrid that makes Lager beer possible