Identificación de microorganismos implicados en la eliminación de nitrógeno en sistemas de tratamiento de aguas residuales mediante técnicas de biología molecular

The identification of the main bacteria populations present in the granular biomass from a biological reactor treating wastewater has been performed by applying two different molecular biology techniques. By means of the DGGE technique five different genera of heterotrophic bacteria (Thiothrix, Thauera, Cloroflexi, Coinamonas y Zoogloea) and one of ammonia oxidizing bacteria (Nitrosomonas) were identified. The FISH technique, based on microscopy, allowed the in situ visualization and quantification of those microorganisms. Special attention was paid to filamentous bacteria distribution (Thiothrix and Cloroflexi) which could exert a structural function in aerobic granular sludge.