Dataset Information

Characterization of the surfaceome of the metal-reducing bacterium Desulfotomaculum reducens

ABSTRACT: Desulfotomaculum reducens strain MI-1 is a Gram-positive, sulfate-reducing bacterium also capable of reducing Fe(III). Metal reduction in Gram-positive bacteria is poorly understood. Here, we investigated Fe(III) reduction with lactate, a non-fermentable substrate, as the electron donor. Lactate consumption is concomitant to Fe(III) reduction, but does not support significant growth, suggesting that little energy can be conserved from this process and that it may occur fortuitously. D. reducens can reduce both soluble (Fe(III)-citrate) and insoluble (hydrous ferric oxide, HFO) Fe(III). Because physically inaccessible HFO was not reduced, we concluded that reduction requires direct contact under these experimental conditions. This implies the presence of a surface exposed reductase capable of transferring electrons from the cell to the extracellular electron acceptor. With the goal of identifying candidate Fe(III) reductases, we carried out an investigation of the surface proteome (surfaceome) of D. reducens. Cell surface exposed proteins were extracted by trypsin cell shaving or by lysozyme treatment, and analyzed by liquid chromatography-tandem mass spectrometry.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Desulfotomaculum Reducens (strain Mi-1)

TISSUE(S): Cell Suspension Culture, Protoplast

SUBMITTER: Romain Hamelin

LAB HEAD: Marc Moniatte

PROVIDER: PXD001072 | Pride | 2014-07-31

REPOSITORIES: Pride

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			Action	DRS
	EV_130902_Qexactive_3ul_RA1.raw	Raw
	EV_130902_Qexactive_3ul_RA2.raw	Raw
	EV_130902_Qexactive_3ul_RA3.raw	Raw
	EV_130902_Qexactive_3ul_RB1.raw	Raw
	EV_130902_Qexactive_3ul_RB2.raw	Raw

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Characterization of the surfaceome of the metal-reducing bacterium Desulfotomaculum reducens.

Dalla Vecchia Elena E Shao Paul P PP Suvorova Elena E Chiappe Diego D Hamelin Romain R Bernier-Latmani Rizlan R

Frontiers in microbiology 20140819

Desulfotomaculum reducens strain MI-1 is a Gram-positive, sulfate-reducing bacterium also capable of reducing Fe(III). Metal reduction in Gram-positive bacteria is poorly understood. Here, we investigated Fe(III) reduction with lactate, a non-fermentable substrate, as the electron donor. Lactate consumption is concomitant to Fe(III) reduction, but does not support significant growth, suggesting that little energy can be conserved from this process and that it may occur fortuitously. D. reducens ...[more]

PMID: 25191310

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