In nature, Saccharomyces yeasts manifest a number of adaptive responses such as filamentation, invasive growth, flocculation or biofilm development to overcome adverse environments. Certain Saccharomyces wild yeasts, namely "flor yeasts", acquired also the ability to form a buoyant biofilm at the broth surface. We have described that mutations in a single gene, identified as FLO11, separate these "floating" yeasts from their non-floating ancestors. We are now involved in studding the regulation of FLO11 and we have described chromating remodelling as a new mechanism involved in FLO11 activation.

 

Identification and analysis of new targets in fungi and new antifungal compounds

Fungi are plant pathogens responsible for most infection and loss in crops, and actually, because the amount of immunocompromised patients, fungal infection in humans has reached worrying levels. Control systems for fungal infection in humans are not developed. In plants, most antifungal compounds are environmental contaminants and are not totally efficient. It is now important to develop new strategies to avoid fungal infection based on identification of new compounds or new targets. In the last years, our group has been involved in the analysis of the mechanism of action for Osmotin, a tobacco antifungal protein, using S. cerevisiae as model. Currently, we are searching for osmotin and other antifungal protein´s targets in plants and human pathogens. We are studing the role for Glycosylation in Ustilago maydis infection, mainly in the dimorphic switch that occur on it. Moreover, we are searching for new antifungal compounds in plant extracts from the Ecuatorian forest. We are mostly interested in those able to inhibit growth by affecting cell cycle, because their putative role as antitumoral agents.