Academic
Publications
Microbially mediated re-oxidation of sulfide during dissimilatory sulfate reduction by Desulfobacter latus

Microbially mediated re-oxidation of sulfide during dissimilatory sulfate reduction by Desulfobacter latus,10.1016/j.gca.2011.03.034,Geochimica Et Cos

Microbially mediated re-oxidation of sulfide during dissimilatory sulfate reduction by Desulfobacter latus   (Citations: 3)
BibTex | RIS | RefWorks Download
Enzymatic reactions during dissimilatory sulfate reduction (DSR) are often treated as unidirectional with respect to dissolved sulfide. However, quantitative models describing kinetic sulfur isotope fractionations during DSR consider the individual enzymatic reactions as reversible (Rees, 1973). Brunner and Bernasconi (2005) extended this line of thought, and suggested that as long as cell external sulfide (CES) concentrations are high enough, CES may diffuse back across the cytoplasmic cell membrane and may subsequently be re-oxidized to sulfate. Here, we test this hypothesis by measuring the time evolution of the δ34S-sulfate signal during DSR in closed system experiments under different levels of sulfide stress (0–20mM and 0–40mM total dissolved sulfide). Our results show that the measured δ34S-sulfate signal is markedly different in the latter case and that the observed sulfate S-isotope time-evolution is incompatible with a Rayleigh type fractionation model. In contrast, our results are consistent with a sulfate reduction and fractionation model that allows for a cell internal oxidation of dissolved sulfide by a sulfate reducer.
Journal: Geochimica Et Cosmochimica Acta - GEOCHIM COSMOCHIM ACTA , vol. 75, no. 12, pp. 3469-3485, 2011
Cumulative Annual
View Publication
The following links allow you to view full publications. These links are maintained by other sources not affiliated with Microsoft Academic Search.
Sort by: