University of Duisburg-Essen, Germany

Since 2014, Rainer Meckenstock is full professor (W3) and head of the Biofilm Centre at the University of Duisburg-Essen as well as scientific director at the IWW, Mülheim (Germany)...

… Before, he was Director of the Institute for Groundwater Ecology at the Helmholtz Center Munich and full professor at the Technical University of Munich, Germany. Rainer’s research interests focus on the elucidation of limitations for microbial degradation processes in the subsurface. At the example of the anaerobic degradation of polycyclic aromatic hydrocarbons (PAHs) the group isolates and describes novel organisms, studies the anaerobic biochemical degradation pathways and elucidates the ecology of PAH degradation in contaminated aquifers. Recently, Rainer discovered life in tiny water droplets in oil reservoirs, which he now uses for studying principles of microbial ecosystem assembly.



Anaerobic degradation of polycyclic aromatic hydrocarbons (PAHs): biochemical principles and ecological limitations

Ivana Kraiselburd1, Meike Arnold1, Xiyang Dong1, Philip Weyrauch1, Rainer U. Meckenstock1,*

1 1University of Duisburg-Essen, Biofilm Centre, Universitätsstr. 5, 45141 Essen, Germany

Polycyclic aromatic hydrocarbons (PAHs) are among the most prevalent and recalcitrant pollutants. PAHs accumulate in sediments and are only very slowly degraded. We enriched several PAHs-degrading cultures with sulfate or iron as terminal electron acceptor. The anaerobic degradation pathways of naphthalene and methylnapthalene were elucidated and the biochemical reactions identified. Naphthalene degradation started with carboxylation as the initial reaction, followed by ring reduction and cleavage. Methylnaphthalene is activated by fumarate addition. After beta-oxidation on the methylene-carbon it follows the 2-naphthoic acid pathway similar to naphthalene degradation. The same biochemical principles were discovered for anaerobic phenanthrene degradation, the largest 3-ring PAH that is know to be degraded anaerobically. In the environment, anaerobic PAH degradation is limited by several factors such as the spacial seperation of electron donors and acceptors. Limiting ecological principles such as the plume-fringe-concept are introduced for polluted aquifers and oil reservoirs.

  1. Dong, X.; Greening, C.; Brüls, T.; Conrad, R.; Guo, K.; Blaskowski, S.; Kaschani, F.; Kaiser, M.; Laban, N. A.; Meckenstock, R. U., Fermentative Spirochaetes mediate necromass recycling in anoxic hydrocarbon-contaminated habitats. ISMEJ 2018. DOI 1038/s41396-018-0148-3
  2. Dong, X.; Jochmann, M. A.; Elsner, M.; Meyer, A. H.; Bäcker, L. E.; Rahmatullah, M.; Schunk, D.; Lens, G.; Meckenstock, R. U., (2017) Monitoring microbial mineralization using reverse stable isotope labeling analysis by Mid-Infrared Laser Spectroscopy. Sci. Technol., 51, 11876-11883.
  3. Weyrauch, P.; Zaytsev, A. V.; Stephan, S.; Kocks, L.; Schmitz, O. J.; Golding, B. T.; Meckenstock, R. U., (2017) Conversion of cis-2-carboxycyclohexylacetyl-CoA in the downstream pathway of anaerobic naphthalene degradation. Microbiol., 19, 2819-2830.
  4. Meckenstock, R. U.; Elsner, M.; Griebler, C.; Lueders, T.; Stumpp, C.; Aamand, J.; Agathos, S. N.; Albrechtsen, H.-J.; Bastiaens, L.; Bjerg, P. L.; Boon, N.; Dejonghe, W.; Huang, W. E.; Schmidt, S. I.; Smolders, E.; Sørensen, S. R.; Springael, D.; and van Breukelen, B. M. (2015) Biodegradation: updating the concepts of control for microbial cleanup in contaminated aquifers. Sci. Technol., 49, 7073-7081.
  5. Meckenstock, R.U., von Netzer, F., Stumpp, C., Lueders, T., Himmelberg, A. M., Hertkorn, N., Schmitt-Kopplin, P., Harir, M., Hosein, R., Haque, S., and Schulze-Makuch, D. (2014) Water droplets in oil are microhabitats for microbial life. Science, 345, 673-676.