Dataset Information

Electric coupling between distant nitrate reduction and sulfide oxidation in marine sediment.

ABSTRACT: Filamentous bacteria of the Desulfobulbaceae family can conduct electrons over centimeter-long distances thereby coupling oxygen reduction at the surface of marine sediment to sulfide oxidation in deeper anoxic layers. The ability of these cable bacteria to use alternative electron acceptors is currently unknown. Here we show that these organisms can use also nitrate or nitrite as an electron acceptor thereby coupling the reduction of nitrate to distant oxidation of sulfide. Sulfidic marine sediment was incubated with overlying nitrate-amended anoxic seawater. Within 2 months, electric coupling of spatially segregated nitrate reduction and sulfide oxidation was evident from: (1) the formation of a 4-6-mm-deep zone separating sulfide oxidation from the associated nitrate reduction, and (2) the presence of pH signatures consistent with proton consumption by cathodic nitrate reduction, and proton production by anodic sulfide oxidation. Filamentous Desulfobulbaceae with the longitudinal structures characteristic of cable bacteria were detected in anoxic, nitrate-amended incubations but not in anoxic, nitrate-free controls. Nitrate reduction by cable bacteria using long-distance electron transport to get privileged access to distant electron donors is a hitherto unknown mechanism in nitrogen and sulfur transformations, and the quantitative importance for elements cycling remains to be addressed.

SUBMITTER: Marzocchi U

PROVIDER: S-EPMC4817607 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Electric coupling between distant nitrate reduction and sulfide oxidation in marine sediment.

Marzocchi Ugo U Trojan Daniela D Larsen Steffen S Meyer Rikke Louise RL Revsbech Niels Peter NP Schramm Andreas A Nielsen Lars Peter LP Risgaard-Petersen Nils N

The ISME journal 20140227 8

Filamentous bacteria of the Desulfobulbaceae family can conduct electrons over centimeter-long distances thereby coupling oxygen reduction at the surface of marine sediment to sulfide oxidation in deeper anoxic layers. The ability of these cable bacteria to use alternative electron acceptors is currently unknown. Here we show that these organisms can use also nitrate or nitrite as an electron acceptor thereby coupling the reduction of nitrate to distant oxidation of sulfide. Sulfidic marine sedi ...[more]

PMID: 24577351

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Dataset Information

Electric coupling between distant nitrate reduction and sulfide oxidation in marine sediment.

Publications

Electric coupling between distant nitrate reduction and sulfide oxidation in marine sediment.

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