INVESTIGADORES
LIBKIND FRATI Diego
congresos y reuniones científicas
Título:
Mycosporines: yeast`s sunscreens?
Autor/es:
LIBKIND FRATI, D; PÉREZ, P; SOMMARUGA, R; DIÉGUEZ, MC; ZAGARESE, H; VAN BROOCK, MR
Lugar:
Rio de Janeiro, Brasil
Reunión:
Congreso; XI International Congress on Yeasts (ICY); 2004
Resumen:
Microbial synthesis of
photoprotective compounds such as carotenoids pigments (antioxidant) and
mycosporines (UV sunscreen) is one of the known strategies to minimize damage
from UV radiation exposure. The production of mycosporines was first detected
in filamentous ascomycetous fungi exposed to UV light, where sporulation
induction appeared to be the main associated effect1. Recently,
mycosporine synthesis was reported to occur in yeasts as well2. A
number of basidiomycetous carotenoid-producing yeast strains grown under photosynthetically active radiation (PAR) synthesized a
UV-absorbing compound showing a maximum absorption at 309-310 nm and identified
as mycosporine-glutaminol-glucoside (MGG) by LC/MS/MS. A higher extent of
mycosporine synthesis was observed when the cells were grown under PAR in
combination with UV radiation. In this study, the ability to produce MGG in 150
(8 genera, 24 species) pigmented yeast strains from Patagonia (Argentina) was
assessed. The strains belong to four taxonomic groups; 1)
Order Sporidiobolales (Class Urediniomycetes), 2) Erythrobasidium clade
(Class Urediniomycetes), 3) Order Cystofilobasidiales (Class Hymenomycetes),
and 4) Tremellales order (Class Hymenomycetes). Induction of mycosporines did
not occur in all pigmented yeast strains tested and it appeared to be a species
related character on yeast members of the Erythrobasidium clade and the
Tremellales. The UV-screening and antioxidant properties attributed to
mycosporines suggest a probable photoprotective role of these compounds in
nature. However, the occurrence of MGG in this yeast group could reflect
phylogenetic relationships among species not strictly related to environmental
factors. The production of mycosporines by yeasts represents an interesting
subject of study due to its novelty and ecological and biotechnological impact.
A wider screening study is being performed to prove mycosporine synthesis as a
chemotaxonomical character to be use in yeast identification and systematics.