INVESTIGADORES
DE GARCIA Virginia
artículos
Título:
Yeasts from an oligotrophic lake in Patagonia (Argentina): diversity, distribution and synthesis of photo-protective compounds and extracellular enzymes
Autor/es:
BRANDAO LUCIANA; LIBKIND DIEGO; VAZ ALINE; ESPÍRITO SANTO LILIA; MOLINÉ MARTÍN; DE GARCIA VIRGINIA; VAN BROOCK MARÍA; ROSA CARLOS
Revista:
FEMS MICROBIOLOGY ECOLOGY
Editorial:
WILEY-BLACKWELL PUBLISHING, INC
Referencias:
Año: 2011 vol. 76 p. 1 - 13
ISSN:
0168-6496
Resumen:
Nahuel Huapi (NH) Lake is an oligotrophic temperate lake of glacial origin with
high transparency, surrounded by well-developed forests and located at San Carlos
de Bariloche, Nahuel Huapi National Park, in Patagonia, Argentina. In this lake, we
characterized yeast distribution and diversity along a south-to-north transect and
established a relationship between the ability to produce photoprotective compounds
(PPCs) (carotenoid pigments and mycosporines) and the occurrence of
yeast at different collection points. Subsurface water samples were filtered for yeast
isolation. Total yeast counts ranged between 22 and 141 CFU L1, and the highest
values corresponded to the most impacted sites. Littoral sites had a low proportion
of yeast-producing PPCs and this group prevailed in pelagic sites. This is probably
a result of the high transparency of the water and the increased UVexposure. The
yeast community from NH Lake showed a high species richness and a uniform
distribution of taxa between pelagic and border collection points. Yeasts were
identified as belonging to 14 genera and 34 species. Rhodotorula mucilaginosa and
Cryptococcus victoriae were the most frequently found species, representing 14.4%
and 13.6% of the total yeast isolates, respectively. Most of the yeast isolates
demonstrated at least one extracellular enzymatic activity (mainly cellulase and
lipase activities), which suggested that these microorganisms are metabolically
active in the lake.