@article {3126,
	title = {Going wireless: Fe(III) oxide reduction without pili by Geobacter sulfurreducens strain JS-1.},
	journal = {Appl Environ Microbiol},
	volume = {80},
	year = {2014},
	month = {2014 Jul},
	pages = {4331-40},
	abstract = {<p>Previous studies have suggested that the conductive pili of Geobacter sulfurreducens are essential for extracellular electron transfer to Fe(III) oxides and for optimal long-range electron transport through current-producing biofilms. The KN400 strain of G. sulfurreducens reduces poorly crystalline Fe(III) oxide more rapidly than the more extensively studied DL-1 strain. Deletion of the gene encoding PilA, the structural pilin protein, in strain KN400 inhibited Fe(III) oxide reduction. However, low rates of Fe(III) reduction were detected after extended incubation (>30 days) in the presence of Fe(III) oxide. After seven consecutive transfers, the PilA-deficient strain adapted to reduce Fe(III) oxide as fast as the wild type. Microarray, whole-genome resequencing, proteomic, and gene deletion studies indicated that this adaptation was associated with the production of larger amounts of the c-type cytochrome PgcA, which was released into the culture medium. It is proposed that the extracellular cytochrome acts as an electron shuttle, promoting electron transfer from the outer cell surface to Fe(III) oxides. The adapted PilA-deficient strain competed well with the wild-type strain when both were grown together on Fe(III) oxide. However, when 50\% of the culture medium was replaced with fresh medium every 3 days, the wild-type strain outcompeted the adapted strain. A possible explanation for this is that the necessity to produce additional PgcA, to replace the PgcA being continually removed, put the adapted strain at a competitive disadvantage, similar to the apparent selection against electron shuttle-producing Fe(III) reducers in many anaerobic soils and sediments. Despite increased extracellular cytochrome production, the adapted PilA-deficient strain produced low levels of current, consistent with the concept that long-range electron transport through G. sulfurreducens biofilms is more effective via pili.</p>},
	keywords = {Adaptation, Physiological, Biofilms, DNA, Bacterial, Electron Transport, Ferric Compounds, Fimbriae Proteins, Fimbriae, Bacterial, Gene Deletion, Geobacter, Oligonucleotide Array Sequence Analysis, Proteomics, Sequence Analysis, DNA},
	issn = {1098-5336},
	doi = {10.1128/AEM.01122-14},
	author = {Smith, Jessica A and Tremblay, Pier-Luc and Shrestha, Pravin Malla and Snoeyenbos-West, Oona L and Franks, Ashley E and Nevin, Kelly P 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}
}
