Detailed project information

In methanogenic environments organic compounds can be completely degraded to CO2 and methane. These degradation processes are found in many places in nature and manmade systems. Bioreactors treating organic waste generate large amounts of methane that can be collected for re-use. In these bioreactors the biomass is immobilised in large aggregates i.e. granular sludge. Consortia of different physiological groups of microorganisms are involved in metanogenic degradation. The microorganisms have strong metabolic interactions, by means of a food web. The later members in the food chain, metanogens, depend on the earlier ones for their substrates, but they also have significant influence on earlier members by removing metabolic products. This interdependence between fermentative and methanogenic microbes is called synthrophy. As a consequence, all microbes have to tune their metabolism, which requires extensive intercellular communication between physiologically diverse species. Information exchange takes place on a physiological level by the exchange of substrates and products. However, it also could involve communication through the exchange of specific signal molecules. Furthermore, the signalling molecules could play a role in aggregation of the syntrophic consortia.

The goal of the proposed research is to study mechanisms by which syntrophic consortia of microorganisms interact. In our investigation we will focus on the influence of specific compounds on growth, viability and aggregation of syntrophic consortia. The genomes of several eubacterial and archaeal species, which are important in syntrophic consortia, have been sequenced. This enables us to integrate physiology, biochemistry and functional genomics. The research may lead to novel insights in mechanisms and principles in the interaction and communication of anaerobes under different environmental conditions.