Recent Origin of the Methacrylate Redox System in Geobacter sulfurreducens AM-1 through Horizontal Gene Transfer.

The origin and evolution of novel biochemical functions remains one of the key questions in molecular evolution. We study recently emerged methacrylate reductase function that is thought to have emerged in the last century and reported in Geobacter sulfurreducens strain AM-1. We report the sequence and study the evolution of the operon coding for the flavin-containing methacrylate reductase (Mrd) and tetraheme cytochrome с (Mcc) in the genome of G.

Desulfopila inferna sp. nov., a sulfate-reducing bacterium isolated from the subsurface of a tidal sand-flat.

A Gram-negative, rod-shaped, sulfate-reducing bacterium (strain JS_SRB250Lac(T)) was isolated from a tidal sand-flat in the German Wadden Sea. 16S rRNA gene sequence analysis showed that strain JS_SRB250Lac(T) belonged to the Desulfobulbaceae (Deltaproteobacteria), with Desulfopila aestuarii MSL86(T) being the closest recognized relative (94.2 % similarity).

Operation of the CO dehydrogenase/acetyl coenzyme A pathway in both acetate oxidation and acetate formation by the syntrophically acetate-oxidizing bacterium Thermacetogenium phaeum.

Thermacetogenium phaeum is a homoacetogenic bacterium that can grow on various substrates, such as pyruvate, methanol, or H2/CO2. It can also grow on acetate if cocultured with the hydrogen-consuming methanogenic partner Methanothermobacter thermautotrophicus. Enzyme activities of the CO dehydrogenase/acetyl coenzyme A (CoA) pathway (CO dehydrogenase, formate dehydrogenase, formyl tetrahydrofolate synthase, methylene tetrahydrofolate dehydrogenase) were detected in cell extracts of pure cultures and of syntrophic cocultures.

Cysteine-mediated electron transfer in syntrophic acetate oxidation by cocultures of Geobacter sulfurreducens and Wolinella succinogenes.

Syntrophic cocultures of Geobacter sulfurreducens and Wolinella succinogenes oxidize acetate with nitrate as terminal electron acceptor. It has been postulated earlier that electrons are transferred in these cocultures not via hydrogen, but via a different carrier, e.g.