Bacterial and archaeal 16S rDNA and 16S rRNA dynamics during an acetate crisis in an anaerobic digestor ecosystem

The dynamics of bacterial and archaeal populations of a laboratory-scale an aerobic digestor were investigated during a crisis period of the process re flected by an accumulation of acetate. A culture-independent approach based on single strand conformation polymorphism (SSCP) analysis of total 16S rD NA and 16S rRNA amplification products was used. A spirochete and a Synergi stes sp. showed high and changing activity levels during the study. A Clost ridium sp, showed a transient increase in presence and activity concomitant with the highest acetate concentrations. A major shirt in the most active archaeal populations from hydrogenotrophic to acetoclastic methanogens prec eded the recovery of the reactor. (C) 2001 Federation of European Microbiol ogical Societies. Published by Elsevier Science B.V. All rights reserved.