INVESTIGADORES
ALVAREZ Hector Manuel
congresos y reuniones científicas
Título:
Vogesella SP. STRAIN EB ISOLATED FROM AN IRON-OXIDIZING AQUIFER OF ANDEAN PATAGONIA IS ABLE TO SECRETE A BLUE PIGMENT WITH ANTIMICROBIAL PROPERTIES
Autor/es:
ARRUA DAY P; ALVAREZ, H. M.
Lugar:
Rosario
Reunión:
Congreso; IX Congreso Argentino de Microbiologia General (SAMIGE); 2013
Institución organizadora:
Sociedad Argentina de Microbiología General (SAMIGE)
Resumen:
In this study, we investigated previously unexplored extreme aquatic environments of Andean Patagonia, Argentina. Oily sheens similar to an oil spill are frequently observed at the surface of water in creeks and small ponds of such places. Chemical analysis of a water sample of these aquifers revealed the occurrence of high concentrations of iron and the presence of a free insoluble pigment, called indigoidine. An indigoidine-producing bacterial strain (strain EB) was isolated from this water sample, which was identified as Vogesella sp. by molecular analysis. Results of this study revealed a previously unrecognized ability among Vogesella genus to oxidize iron coupled with nitrate reduction, suggesting an active role of strain EB in the investigated iron-oxidizing ecosystem. The production of the blue pigment by Vogesella sp. strain EB depended on the cell growth at cold temperatures (below 15º C), as well as on the attachment of cells to solid surfaces during their cultivation at 28º C. The indigoidine pigment produced by strain EB showed an inhibitory effect on the growth on diverse microorganisms, such as Escherichia coli, Staphylococcus aureus and Candida albicans, but not on Rhodococcus opacus and Rhodotorula sp.. Collectively, results of this study suggested that the prevailing conditions of aquifers of Andean Patagonia are favorable for indigoidine biosynthesis and release into the environment by iron-oxidizing bacteria like strain EB. The presence of free indigoidine at the surface of water in natural environments may contribute with the reduction of microbial colonizers that compete for nutrients, and, to some extent, with the modulation of the microbial diversity and community composition in the aquifers of Andean Patagonia.
