PEREZ Alejandra patricia
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Photoprotective compounds (carotenoids and MAAs) in freshwater patagonian yeasts
DIEGO LIBKIND; PATRICIA PÉREZ; RUBÉN SOMMARUGA; MARÍA DEL CARMEN DIÉGUEZ; MARCELA FERRARO; SILVIA BRIZZIO; HORACIO ZAGARESE; MARÍA ROSA GIRAUDO
Otro; XXXIX Encuentro anual de la Sociedad Argentina de Investigaciones en Bioquímica y Biología molecular; 2003
Sociedad Argentina de iNvestigaciones en Bioquímica y Biología Molecular
The synthesis of carotenoids and/or mycosporine-like amino acids (MAAs) which have respectively antioxidant and UVR sunscreen properties is a common strategy in the photoprotection of microorganisms. The production of these compounds by freshwater yeast strains grown under PAR and UVR was assessed. In most red species, caretonoid synthesis was stimulated under PAR or UVR+PAR irradiation. This response was higher when constitutive levels of pigments (in the dark) were lower. This suggests that cells with higher constitutive levels of carotenoids are less responsive to induction by UVR-PAR. Four yeast strains were able to produce a UV-absorbing compound (309-310 nm) when exposed to PAR or UV-PAR identified as mycosporine-glutaminol-glucoside This is the first time that the production of MAAs by yeasts is reported. All strains that developed under UVR-PAR were able to synthesize carotenoids either constitutively or in response to PAR exposure, and a few of them also produced MAAs. Collectively, our results suggest that the presence of carotenoids, either alone or in combination with MAAs, are required for sustaining yeast growth under exposure to UVR-PAR.