Brettanomyces/Dekkera, a novel model organism to elucidate yeast evolution and comparative genomics.
Jure Piskur (1), Jouzas Siurkus (2), Mikael R. Andersen (2), Gloria Joergensen (2), Ela Rozpedowska (1), Silvia Polakova (3), Anamaria Merico (4), Ileana Vigentini (4), Pavol Sulo (5), Dorte Joerck-Ramberg (2), Ken Wolfe (6), Concetta Compagno (4)
(1) Cell and Organism Biology, Lund University, Soelvegatan 35, Lund, 22362, Sweden; (2) Technical University of Denmark; (3) Technical University of Denamrk and Comenius University, Bratislava; (4) University of Milan; (5) Comenius University, Bratislava; (6) Trinity College, Dublin
Saccharomyces/Kluyveromyces (S/K) yeasts have a number of unusual characters. S. cerevisiae (Sc) primarily degrades sugars to ethanol and has the ability to grow without oxygen. We are interested in how the progenitor of Sc developed these basic characters and whether the molecular mechanisms employed during their evolution were unique. Brettanomyces/Dekkera (B/D) yeasts can be found in similar environments as S/K yeasts, and they are involved in wine spoilage. They separated from the S/K progenitor ~200-300 Mya, much before the Sc lineage duplicated its genome and adopted foreign genes as the background to develop the present life-style. We studied the phylogenetic relationship among B/D isolates and found two clear sub-families: one including D. bruxellensis having in general over 5 chromosomes, and another including B. naardensis having only 4-5 chromosomes. When B/D yeasts were studied in batch fermentors, Db showed glucose repression and Crabtree effect, while Bn is Crabtree-negative. Furthermore, Db showed the ability to grow in anaerobiosis and could generate mitochondrial petite mutants, while the other sub-family needs oxygen and is petite-negative. A similar pattern of traits and division into two sub-families have also been observed among S/K, and therefore suggests a parallel evolution. We would like to understand if both yeast groups have used the same molecular strategies during their evolutionary history to achieve the expression of similar modern phenotypes.