Mycosporines in carotenogenic yeasts.

The ability to produce mycosporines (MYCs) in 157 pigmented yeast strains (eight genera, 25 species) isolated from natural environments of Patagonia (Argentina) was assessed. The strains belong to four taxonomic groups: the Sporidiobolales and Erythrobasidium clade of the class Urediniomycetes, and Cystofilobasidiales and Tremellales of the class Hymenomycetes. Induction of MYCs did not occur in all yeast strains tested and appeared to be an exclusive trait of members of the Erythrobasidium clade and Tremellales. This is the first report on the production of MYCs by pigmented species from the latter group, as well as the first extensive screening of mycosporinogenic yeasts. The consistent occurrence of MYCs in some specific phylogenetic groups suggests this trait bears evolutionary significance and that the presence/absence of MYCs may have potential applications in yeast systematics.