Anaerobic benzene degradation by bacteria
Article first published online: 30 MAR 2011
© 2011 The Authors; Journal compilation © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd
Volume 4, Issue 6, pages 710–724, November 2011
How to Cite
Vogt, C., Kleinsteuber, S. and Richnow, H.-H. (2011), Anaerobic benzene degradation by bacteria. Microbial Biotechnology, 4: 710–724. doi: 10.1111/j.1751-7915.2011.00260.x
- Issue published online: 14 OCT 2011
- Article first published online: 30 MAR 2011
- Received 13 September, 2010; accepted 18 February, 2011.
Benzene is a widespread and toxic contaminant. The fate of benzene in contaminated aquifers seems to be primarily controlled by the abundance of oxygen: benzene is aerobically degraded at high rates by ubiquitous microorganisms, and the oxygen-dependent pathways for its breakdown were elucidated more than 50 years ago. In contrast, benzene was thought to be persistent under anoxic conditions until 25 years ago. Nevertheless, within the last 15 years, several benzene-degrading cultures have been enriched under varying electron acceptor conditions in laboratories around the world, and organisms involved in anaerobic benzene degradation have been identified, indicating that anaerobic benzene degradation is a relevant environmental process. However, only a few benzene degraders have been isolated in pure culture so far, and they all use nitrate as an electron acceptor. In some highly enriched strictly anaerobic cultures, benzene has been described to be mineralized cooperatively by two or more different organisms. Despite great efforts, the biochemical mechanism by which the aromatic ring of benzene is activated in the absence of oxygen is still not fully elucidated; methylation, hydroxylation and carboxylation are discussed as likely reactions. This review summarizes the current knowledge about the ‘key players’ of anaerobic benzene degradation under different electron acceptor conditions and the possible pathway(s) of anaerobic benzene degradation.