INVESTIGADORES
DIEGUEZ maria Del carmen
artículos
Título:
Occurrence of photoprotective Compounds in Yeasts from Freshwater Ecosystems of Northwestern Patagonia.
Autor/es:
LIBKIND, D; DIÉGUEZ, MC; MOLINÉ, M.; PÉREZ, P; ZAGARESE & M. VAN BROOCK
Revista:
PHOTOCHEMISTRY AND PHOTOBIOLOGY
Editorial:
Allen Press
Referencias:
Año: 2006
ISSN:
0031-8655
Resumen:
In this paper we present the results of the research on the occurrence, induction and role of photoprotective compounds (PPCs) present in native aquatic yeasts from freshwater Patagonian ecosystems. We focus on the effect of ultraviolet radiation (UVR) as a factor controlling the level of photoprotection of yeasts, and explore its potential significance in shaping yeast distributional patterns. The research presented here combines field surveys and laboratory work, including the isolation and culture of native yeasts strains as well as laboratory assays under different radiation conditions. The results obtained suggest that yeasts are common dwellers of oligotrophic  Patagonian water bodies, and provide the first evidence of distribution of PPC (carotenoid and mycosporine) producing yeasts in temperate freshwaters. A greater proportion of carotenogenic yeasts was observed in high elevation lakes. The yeasts strains isolated from these environments were found to produce higher amounts of mycosporines (MYC) presenting also higher tolerance to UVB exposure than those from piedmont lakes. Patagonian yeasts have only one type of MYC: mycosporine-glutaminol-glucoside (myc-glu-glu), a fact which seems common to all other yeasts. By analysing the production of myc-glu-glu in a large number of yeasts belonging to different taxonomic groups, we propose that this compound may have a potential use as chemotaxonomic marker in yeast systematics. Collectively, our work reveals that in Patagonian freshwater yeasts there is an apparent relationship between the ability to produce PPCs, their tolerance to UV exposure and their success in colonizing habitats highly exposed to UVR.