@article {1421,
	title = {Biodegradation of low concentrations of 1,2-dibromoethane in groundwater is enhanced by phenol.},
	journal = {Appl Microbiol Biotechnol},
	volume = {98},
	year = {2014},
	month = {2014 Feb},
	pages = {1329-38},
	abstract = {<p>The lead scavenger 1,2-dibromoethane (EDB), a former additive to leaded gasoline, is a common groundwater contaminant, yet not much knowledge is available for its targeted bioremediation, especially under in situ conditions. The study site was an aviation gas spill site, which, although all hydrocarbons and most of the EDB were remediated in the mid-1990s, still exhibits low levels of EDB remaining in the groundwater (about 11 \&mu;g EDB/l). To evaluate the effect of phenol on biostimulation of low concentration of EDB, microcosms were established from an EDB-contaminated aquifer. After 300 days at environmentally relevant conditions (12\&thinsp;\&plusmn;\&thinsp;2 \&deg;C, static incubation), EDB was not significantly removed from unamended microcosms compared to the abiotic control. However, in treatments amended with phenol, up to 80 \% of the initial EDB concentration had been degraded, while added phenol was removed completely. Microbial community composition in unamended and phenol-amended microcosms remained unchanged, and Polaromonas sp. dominated both types of microcosms, but total bacterial abundance and numbers of the gene for phenol hydroxylase were higher in phenol-amended microcosms. Dehalogenase, an indicator suggesting targeted aerobic biodegradation of EDB, was not detected in either treatment. This finding suggests phenol hydroxylase, rather than a dehalogenation reaction, may be responsible for 1,2-dibromoethane oxidation under in situ conditions. In addition, biostimulation of EDB is possible through the addition of low levels of phenol in aerobic groundwater sites.</p>
},
	keywords = {Bacteria, Biota, Ethylene Dibromide, Groundwater, Metabolic Networks and Pathways, Phenol, Water Pollutants},
	issn = {1432-0614},
	doi = {10.1007/s00253-013-4963-1},
	author = {Baek, Kyunghwa and Wang, Meng and McKeever, Robert and Rieber, Kahlil and Park, Chul and N{\"u}sslein, Klaus}
}
@article {3136,
	title = {Anaerobic benzene oxidation via phenol in Geobacter metallireducens.},
	journal = {Appl Environ Microbiol},
	volume = {79},
	year = {2013},
	month = {2013 Dec},
	pages = {7800-6},
	abstract = {<p>Anaerobic activation of benzene is expected to represent a novel biochemistry of environmental significance. Therefore, benzene metabolism was investigated in Geobacter metallireducens, the only genetically tractable organism known to anaerobically degrade benzene. Trace amounts (<0.5 μM) of phenol accumulated in cultures of Geobacter metallireducens anaerobically oxidizing benzene to carbon dioxide with the reduction of Fe(III). Phenol was not detected in cell-free controls or in Fe(II)- and benzene-containing cultures of Geobacter sulfurreducens, a Geobacter species that cannot metabolize benzene. The phenol produced in G. metallireducens cultures was labeled with (18)O during growth in H2(18)O, as expected for anaerobic conversion of benzene to phenol. Analysis of whole-genome gene expression patterns indicated that genes for phenol metabolism were upregulated during growth on benzene but that genes for benzoate or toluene metabolism were not, further suggesting that phenol was an intermediate in benzene metabolism. Deletion of the genes for PpsA or PpcB, subunits of two enzymes specifically required for the metabolism of phenol, removed the capacity for benzene metabolism. These results demonstrate that benzene hydroxylation to phenol is an alternative to carboxylation for anaerobic benzene activation and suggest that this may be an important metabolic route for benzene removal in petroleum-contaminated groundwaters, in which Geobacter species are considered to play an important role in anaerobic benzene degradation.</p>},
	keywords = {Anaerobiosis, Benzene, Carbon Dioxide, Gene Deletion, Gene Expression Profiling, Geobacter, Iron, Metabolic Networks and Pathways, Oxidation-Reduction, Phenol, Water},
	issn = {1098-5336},
	doi = {10.1128/AEM.03134-13},
	author = {Zhang, Tian and Tremblay, Pier-Luc and Chaurasia, Akhilesh Kumar and Smith, Jessica A and Bain, Timothy S and Lovley, Derek R}
}
@article {419,
	title = {Genome-scale analysis of anaerobic benzoate and phenol metabolism in the hyperthermophilic archaeon Ferroglobus placidus.},
	journal = {ISME J},
	volume = {6},
	year = {2012},
	month = {2012 Jan},
	pages = {146-57},
	abstract = {Insight into the mechanisms for the anaerobic metabolism of aromatic compounds by the hyperthermophilic archaeon Ferroglobus placidus is expected to improve understanding of the degradation of aromatics in hot (>80{\textdegree} C) environments and to identify enzymes that might have biotechnological applications. Analysis of the F. placidus genome revealed genes predicted to encode enzymes homologous to those previously identified as having a role in benzoate and phenol metabolism in mesophilic bacteria. Surprisingly, F. placidus lacks genes for an ATP-independent class II benzoyl-CoA (coenzyme A) reductase (BCR) found in all strictly anaerobic bacteria, but has instead genes coding for a bzd-type ATP-consuming class I BCR, similar to those found in facultative bacteria. The lower portion of the benzoate degradation pathway appears to be more similar to that found in the phototroph Rhodopseudomonas palustris, than the pathway reported for all heterotrophic anaerobic benzoate degraders. Many of the genes predicted to be involved in benzoate metabolism were found in one of two gene clusters. Genes for phenol carboxylation proceeding through a phenylphosphate intermediate were identified in a single gene cluster. Analysis of transcript abundance with a whole-genome microarray and quantitative reverse transcriptase polymerase chain reaction demonstrated that most of the genes predicted to be involved in benzoate or phenol metabolism had higher transcript abundance during growth on those substrates vs growth on acetate. These results suggest that the general strategies for benzoate and phenol metabolism are highly conserved between microorganisms living in moderate and hot environments, and that anaerobic metabolism of aromatic compounds might be analyzed in a wide range of environments with similar molecular targets.},
	keywords = {Acetates, Archaea, Bacteria, Anaerobic, Benzoates, Metabolic Networks and Pathways, Phenol, Rhodopseudomonas},
	issn = {1751-7370},
	doi = {10.1038/ismej.2011.88},
	author = {Holmes, Dawn E and Risso, Carla and Smith, Jessica A and Lovley, Derek R}
}
