The POLLOX Project: Anaerobic Pollutant Degradation with Oxygen

POLLOX is an ERC Consolidator Project (2014 - 2019) funded within the 7th Framework Programme of the European Commission. The project aims to question established paradigms on the role of molecular oxygen in what is currently considered as anaerobic pollutant degradation. Two central paradigms are currently understood to control biodegradation in groundwater and sediments: (i) Redox gradients and interphases between compartments are 'hot-spots' of for contaminant breakdown, and (ii) biodegradation is primarily limited by local electron acceptor availability, in particular that of oxygen.

The hypotheses at the heart of the POLLOX project originate from a combination of own recent findings, partially inconsistent with the current understanding of process and degrader stratification at redox gradients. POLLOX postulates that oxygen-dependent degradation of pollutants in anaerobic compartments is possible by two unrecognised physiological adaptations of microbes. We aim to verify the hypothesis that filamentous Desulfobulbaceae and other so-called "cable bacteria" can be involved in the anaerobic oxidation of pollutants via long-distance electron transfer to oxygen across redox gradients. Furthermore, we postulate that oxygenase-dependent degraders and catabolic pathways, in absence of external oxygen, can be active in reduced compartments via self-sustained oxydantogenesis e.g. by nitric oxide dismutation.

The objectives of POLLOX have the potential to revolutionise the current perception of the role and relevance of molecular oxygen as an agent in biogeochemical processes at redox gradients, including contaminant degradation groundwater. Both investigated ecological mechanisms of long-distance electron transfer and "intra-aerobic" catabolic pathways are nascent fields, which may span widely into novel applications or management options in water and soil protection, and also the anaerobic human microbiome.

POLLOX Publications

  • Lueders T (2017) The ecology of anaerobic degraders of BTEX hydrocarbons in aquifers. FEMS Microbiol Ecol 93. Doi: 10.1093/femsec/fiw220. [Abstract]
  • Lueders T, Dumont MG, Bradford L & Manefield M (2016) RNA-stable isotope probing: From carbon flow within key microbiota to targeted transcriptomes. Curr Opin Biotechnol 41: 83-89. [Abstract]
  • Müller H, Bosch J, Griebler C, Damgaard LR, Nielsen LP, Lueders T & Meckenstock RU (2016) Long-distance electron transfer by cable bacteria in aquifer sediments. ISME J doi: 10.1038/ismej.2015.1250. [Abstract]