Ferroglobus placidus gen. nov., sp. nov., a novel hyperthermophilic archaeum that oxidizes Fe 2+ at neutral pH under anoxic conditions

Hafenbradl, Doris; Keller, Martin; Dirmeier, Reinhard; Rachel, Reinhard; Rossnagel, P.; Burggraf, Siegfried; Huber, Harald; Stetter, Karl O.

doi:10.1007/s002030050388

Cited by 300 publications

(262 citation statements)

References 0 publications

Supporting

Mentioning

256

Contrasting

Unclassified

Order By: Relevance

“…However, F. placidus is a strict anaerobe (Hafenbradl et al, 1996), and no genes for aerobic metabolism of benzoate via hydroxylation or the BOX pathway (Zaar et al, 2001;Gescher et al, 2002;Risso et al, 2009) were apparent in the genome. Multiple anaerobic BCLs have also been detected in other organisms.…”

Section: Resultsmentioning

confidence: 99%

“…Aromatic compounds have been detected in sediments associated with hydrothermal vent sites and petroleum reservoirs (Simoneit and Lonsdale, 1982;Bazylinski et al, 1989;Mangani et al, 1991;Goetz and Jannasch, 1993;Magot et al, 2000;Culotta et al, 2007). Previous studies have also shown that benzoate can be oxidized to 14 CO 2 in hot sediments from the same general location in Vulcano, Italy, where F. placidus was isolated (Hafenbradl et al, 1996;. Although sulfate reduction appeared to be the predominant terminal electron-accepting process in those sediments, additions of molybdate, which inhibited sulfate reduction, did not inhibit benzoate oxidation.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Genome-scale analysis of anaerobic benzoate and phenol metabolism in the hyperthermophilic archaeon Ferroglobus placidus

et al. 2011

View full text Add to dashboard Cite

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° 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.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Genome-scale analysis of anaerobic benzoate and phenol metabolism in the hyperthermophilic archaeon Ferroglobus placidus

et al. 2011

View full text Add to dashboard Cite

show abstract

“…Only one archaeal putative reductive dehalogenase gene has been identified to date from a Ferroglobus species [59], but this organism has not been demonstrated to conserve energy via organohalide respiration. Most, but not all, of these rdhA gene-carrying organisms are known to reduce halogenated organic compounds.…”

Section: Reductive Dehalogenasesmentioning

confidence: 99%

Overview of organohalide-respiring bacteria and a proposal for a classification system for reductive dehalogenases

Hug

Maphosa

Leys

et al. 2013

Phil. Trans. R. Soc. B

273

277

View full text Add to dashboard Cite

Organohalide respiration is an anaerobic bacterial respiratory process that uses halogenated hydrocarbons as terminal electron acceptors during electron transport-based energy conservation. This dechlorination process has triggered considerable interest for detoxification of anthropogenic groundwater contaminants. Organohalide-respiring bacteria have been identified from multiple bacterial phyla, and can be categorized as obligate and non-obligate organohalide respirers. The majority of the currently known organohalide-respiring bacteria carry multiple reductive dehalogenase genes. Analysis of a curated set of reductive dehalogenases reveals that sequence similarity and substrate specificity are generally not correlated, making functional prediction from sequence information difficult. In this article, an orthologue-based classification system for the reductive dehalogenases is proposed to aid integration of new sequencing data and to unify terminology.

show abstract

“…Bacterial species that couple the oxidation of Fe(II) to nitrate reduction have been isolated from a wide range of habitats and are phylogenetically diverse, indicating their environmental prevalence and importance (5,9,10). Recently, species of the genus Acidovorax have dominated enrichment cultures and been isolated as proficient nitrate-dependent Fe(II) oxidizers (11)(12)(13)(14); however, even Escherichia coli has been demonstrated to be capable of Fe(II) oxidation coupled to nitrate reduction (15).…”

mentioning

confidence: 99%

Fe(II) Oxidation Is an Innate Capability of Nitrate-Reducing Bacteria That Involves Abiotic and Biotic Reactions

Carlson

Clark²,

Blazewicz³

et al. 2013

Journal of Bacteriology

155

160

View full text Add to dashboard Cite

Phylogenetically diverse species of bacteria can catalyze the oxidation of ferrous iron [Fe(II)] coupled to nitrate (NO 3؊ ) reduction, often referred to as nitrate-dependent iron oxidation (NDFO). Very little is known about the biochemistry of NDFO, and though growth benefits have been observed, mineral encrustations and nitrite accumulation likely limit growth. Acidovorax ebreus, like other species in the Acidovorax genus, is proficient at catalyzing NDFO. Our results suggest that the induction of specific Fe(II) oxidoreductase proteins is not required for NDFO. No upregulated periplasmic or outer membrane redox-active proteins, like those involved in Fe(II) oxidation by acidophilic iron oxidizers or anaerobic photoferrotrophs, were observed in proteomic experiments. We demonstrate that while "abiotic" extracellular reactions between Fe(II) and biogenic NO 2 ؊ /NO can be involved in NDFO, intracellular reactions between Fe(II) and periplasmic components are essential to initiate extensive NDFO. We present evidence that an organic cosubstrate inhibits NDFO, likely by keeping periplasmic enzymes in their reduced state, stimulating metal efflux pumping, or both, and that growth during NDFO relies on the capacity of a nitrate-reducing bacterium to overcome the toxicity of Fe(II) and reactive nitrogen species. On the basis of our data and evidence in the literature, we postulate that all respiratory nitrate-reducing bacteria are innately capable of catalyzing NDFO. Our findings have implications for a mechanistic understanding of NDFO, the biogeochemical controls on anaerobic Fe(II) oxidation, and the production of NO 2 ؊ , NO, and N 2 O in the environment.

show abstract

Ferroglobus placidus gen. nov., sp. nov., a novel hyperthermophilic archaeum that oxidizes Fe 2+ at neutral pH under anoxic conditions

Cited by 300 publications

References 0 publications

Genome-scale analysis of anaerobic benzoate and phenol metabolism in the hyperthermophilic archaeon Ferroglobus placidus

Genome-scale analysis of anaerobic benzoate and phenol metabolism in the hyperthermophilic archaeon Ferroglobus placidus

Overview of organohalide-respiring bacteria and a proposal for a classification system for reductive dehalogenases

Fe(II) Oxidation Is an Innate Capability of Nitrate-Reducing Bacteria That Involves Abiotic and Biotic Reactions

Contact Info

Product

Resources

About