Morphology and physiology of colonies of wild Saccharomyces cerevisiae strains.
Vratislav Stovicek (1), Libuse Vachova (2), Zdena Palkova (1)
(1) Dept. Genetics and Microbiol., Charles University, Vinicna 5, Prague, 12844, Czech Republic; (2) Institute of Microbiology, Academy of Sciences, Videnska 1083, Prague, 14220, Czech Republic
In contrast to laboratory strains, various Saccharomyces cerevisiae strains isolated from nature have capability to form colonies with highly structured morphology. Previously, we characterized properties of fluffy colonies formed by the wild strain BR-F and also capability of this strain to switch under laboratory conditions to domesticated variants creating smooth colonies (Kuthan et al., Mol. Microbiol. 47(3):745-54, 2003). The other three S. cerevisiae strains isolated from various natural environments also create structured colonies of even several different morphotypes. In this work, we characterized ten colony morphotypes in terms of cell morphology and cell budding pattern. In parallel, we investigated changes in protein composition of extracellular matrix during colony development as well as changes in expression of genes possibly involved in processes connected with morphogenesis. These include genes involved in flocculation, pseudohyphal differentiation, cell surface properties and sugar metabolism. Our results show significant differences not only among unrelated wild strains, but also differences among individual colony morphotypes of the particular strain. The data confirm principal difference in colony growth, development and properties of wild and domesticated strains. This work was supported by grants 204/03/H066 and IAA500200506.