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Published on: December 7, 2021
Anaerobic benzene degradation by bacteria
Carsten Vogt1, Sabine Kleinsteuber, Hans-Hermann Richnow
1Department of Isotope Biogeochemistry, UFZ - Helmholtz Centre for Environmental Research, Leipzig, Germany. carsten.vogt@ufz.de
Microbial Biotechnology
|April 1, 2011
Summary
Anaerobic benzene degradation, once thought impossible, is now a proven environmental process. Microbes can break down benzene without oxygen, though the exact biochemical pathways are still under investigation.
Area of Science:
- Environmental microbiology
- Biogeochemistry
- Contaminant remediation
Background:
- Benzene is a toxic contaminant found in aquifers.
- Aerobic benzene degradation is well-understood.
- Anaerobic benzene degradation was previously considered unlikely but is now recognized as relevant.
Purpose of the Study:
- To review current knowledge on anaerobic benzene degradation.
- To identify key microbial players under various electron acceptor conditions.
- To discuss potential biochemical pathways for benzene ring activation.
Main Methods:
- Enrichment of benzene-degrading microbial cultures under anaerobic conditions.
- Isolation and identification of benzene-degrading microorganisms.
- Review of existing literature on anaerobic benzene metabolism.
Main Results:
- Several microbial cultures capable of anaerobic benzene degradation have been identified.
- Organisms using nitrate as an electron acceptor have been isolated in pure culture.
- Cooperative degradation by multiple organisms has been observed in some cultures.
Conclusions:
- Anaerobic benzene degradation is an important process in contaminated environments.
- Nitrate reducers are among the identified benzene degraders.
- The precise biochemical mechanism of anaerobic benzene activation requires further elucidation, with methylation, hydroxylation, and carboxylation as proposed initial steps.
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