@article {605,
	title = {Humics as an electron donor for anaerobic respiration.},
	journal = {Environ Microbiol},
	volume = {1},
	year = {1999},
	month = {1999 Feb},
	pages = {89-98},
	abstract = {The possibility that microorganisms might use reduced humic substances (humics) as an electron donor for the reduction of electron acceptors with a more positive redox potential was investigated. All of the Fe(III)- and humics-reducing microorganisms evaluated were capable of oxidizing reduced humics and/or the reduced humics analogue anthrahydroquinone-2,6,-disulphonate (AHODS), with nitrate and/or fumarate as the electron acceptor. These included Geobacter metallireducens, Geobacter sulphurreducens, Geothrix fermentans, Shewanella alga, Wolinella succinogenes and {\textquoteright}S. barnesii{\textquoteright}. Several of the humics-oxidizing microorganisms grew in medium with AHQDS as the sole electron donor and fumarate as the electron acceptor. Even though it does not reduce Fe(III) or humics, Paracoccus denitrificans could use AHQDS and reduced humics as electron donors for denitrification. However, another denitrifier, Pseudomonas denitrificans, could not. AHODS could also serve as an electron donor for selenate and arsenate reduction by W. succinogenes. Electron spin resonance studies demonstrated that humics oxidation was associated with the oxidation of hydroquinone moieties in the humics. Studies with G. metallireducens and W. succinogenes demonstrated that the anthraquinone-2,6-disulphonate (AQDS)/AHQDS redox couple mediated an interspecies electron transfer between the two organisms. These results suggest that, as microbially reduced humics enter less reduced zones of soils and sediments, the reduced humics may serve as electron donors for microbial reduction of several environmentally significant electron acceptors.},
	keywords = {Aerobiosis, Anaerobiosis, Anthraquinones, Arsenates, Bacteria, Electron Transport, Fumarates, Humic Substances, Selenium Compounds, Tumor Cells, Cultured},
	issn = {1462-2912},
	author = {Lovley, D R and Fraga, J L and Coates, J D and Blunt-Harris, E L}
}
@article {625,
	title = {Recovery of humic-reducing bacteria from a diversity of environments.},
	journal = {Appl Environ Microbiol},
	volume = {64},
	year = {1998},
	month = {1998 Apr},
	pages = {1504-9},
	abstract = {To evaluate which microorganisms might be responsible for microbial reduction of humic substances in sedimentary environments, humic-reducing bacteria were isolated from a variety of sediment types. These included lake sediments, pristine and contaminated wetland sediments, and marine sediments. In each of the sediment types, all of the humic reducers recovered with acetate as the electron donor and the humic substance analog, 2,6-anthraquinone disulfonate (AQDS), as the electron acceptor were members of the family Geobacteraceae. This was true whether the AQDS-reducing bacteria were enriched prior to isolation on solid media or were recovered from the highest positive dilutions of sediments in liquid media. All of the isolates tested not only conserved energy to support growth from acetate oxidation coupled to AQDS reduction but also could oxidize acetate with highly purified soil humic acids as the sole electron acceptor. All of the isolates tested were also able to grow with Fe(III) serving as the sole electron acceptor. This is consistent with previous studies that have suggested that the capacity for Fe(III) reduction is a common feature of all members of the Geobacteraceae. These studies demonstrate that the potential for microbial humic substance reduction can be found in a wide variety of sediment types and suggest that Geobacteraceae species might be important humic-reducing organisms in sediments.},
	keywords = {Acetic Acid, Anthraquinones, Base Sequence, DNA Primers, Electron Transport, Fresh Water, Gram-Negative Anaerobic Bacteria, Humic Substances, Iron, Molecular Sequence Data, Phylogeny, Polymerase Chain Reaction, RNA, Bacterial, RNA, Ribosomal, 16S, Seawater, Sulfur-Reducing Bacteria, Water Microbiology},
	issn = {0099-2240},
	author = {Coates, J D and Ellis, D J and Blunt-Harris, E L and Gaw, C V and Roden, E E and Lovley, D R}
}
@article {637,
	title = {Desulfuromonas palmitatis sp. nov., a marine dissimilatory Fe(III) reducer that can oxidize long-chain fatty acids.},
	journal = {Arch Microbiol},
	volume = {164},
	year = {1995},
	month = {1995 Dec},
	pages = {406-13},
	abstract = {Studies on the microorganisms living in hydrocarbon-contaminated sediments in San Diego Bay, California led to the isolation of a novel Fe(III)-reducing microorganism. This organism, designated strain SDBY1, was an obligately anaerobic, non-motile, non-flagellated, gram-negative rod. Strain SDBY1 conserves energy to support growth from the oxidation of acetate, lactate, succinate, fumarate, laurate, palmitate, or stearate. H2 was also oxidized with the reduction of Fe(III), but growth with H2 as the sole electron donor was not observed. In addition to various forms of soluble and insoluble Fe(III), strain SDBY1 also coupled growth to the reduction of fumarate, Mn(IV), or S0. Air-oxidized minus dithionite-reduced difference spectra exhibited peaks at 552.8, 523.6, and 422.8 nm, indicative of c-type cytochrome(s). Strain SDBY1 shares physiological characteristics with organisms in the genera Geobacter, Pelobacter, and Desulfuromonas. Detailed analysis of the 16S rRNA sequence indicated that strain SDBY1 should be placed in the genus Desulfuromonas. The new species name Desulfuromonas palmitatis is proposed. D. palmitatis is only the second marine organism found (after D. acetoxidans) to oxidize multicarbon organic compounds completely to carbon dioxide with Fe(III) as an electron acceptor and provides the first pure culture model for the oxidation of long-chain fatty acids coupled to Fe(III) reduction.},
	keywords = {Electron Transport, Fatty Acids, Gram-Negative Anaerobic Bacteria, Iron, Microscopy, Electron, Scanning, Oxidation-Reduction, Phylogeny, RNA, Bacterial, RNA, Ribosomal, 16S, Water Microbiology},
	issn = {0302-8933},
	author = {Coates, J D and Lonergan, D J and Philips, E J and Jenter, H and Lovley, D R}
}
