Methanogenesis in wetlands is dependent on intermediary substrates derived from the degradation of biopolymers. Formate is one such substrate and is stimulatory to methanogenesis and acetogenesis in anoxic microcosms of soil from the fen Schlöppnerbrunnen. Formate dissimilation also yields CO(2) as a potential secondary substrate. The objective of this study was to resolve potential differences...

The effect of the addition of trimethylamine N-oxide (TMAO) in the growth medium on Escherichia coli anaerobic fermentative and respiratory pathways was examined. Formate dehydrogenase H (FDH-H) activity was totally repressed by the addition of 40 mM TMAO, whereas the overall hydrogenase (HYD) activity was reduced by 25%. Accordingly, expression of lacZ operon fusions with the fdhF and hycB str...

The catabolism of sodium formate to acetate and carbon dioxide by the anaerobic acetogen Butyribacterium methylotrophicum was analyzed by fermentation time course and 13C nuclear magnetic resonance studies. Significant hydrogen production and consumption fluxes were observed during formate catabolism but not during the catabolism of formate plus CO. In the latter case, formate and CO were simul...

Formate dehydrogenase (FDH) is involved in various higher plant abiotic stress responses. Here, we investigated the role of rice bean (Vigna umbellata) VuFDH in Al and low pH (H(+)) tolerance. Screening of various potential substrates for the VuFDH protein demonstrated that it functions as a formate dehydrogenase. Quantitative reverse transcription-PCR and histochemical analysis showed that the...

NAD+-dependent formate dehydrogenase was screened in various bacterial strains. Facultative methanol-utilizing bacteria isolated from soil samples, acclimated to a medium containing methanol and formate at pH 9.5, were classified as members of the genus Moraxella. From a crude extract of Moraxella sp. strain C-1, formate dehydrogenase was purified to homogeneity, as judged by disc gel electroph...

[Ni(P(R)(2)N(R')(2))(2)(CH(3)CN)](2+) complexes with R = Ph, R' = 4-MeOPh or R = Cy, R' = Ph , and a mixed-ligand [Ni(P(R)(2)N(R')(2))(P(R''(2))N(R'(2)))(CH(3)CN)](2+) with R = Cy, R' = Ph, R'' = Ph, have been synthesized and characterized by single-crystal X-ray crystallography. These and previously reported complexes are shown to be electrocatalysts for the oxidation of formate in solution to...

Ethyl formate, a volatile solvent, has insecticidal and fungicidal properties and is suggested as a potential fumigant for stored crop and fruit. Its primary contact route is through the respiratory tract; however, reliable repeated toxicological studies focusing on the inhalation route have not been published to date. Therefore, the present study was conducted to investigate the safety of a 90...

Engineering the level of metabolic cofactors to manipulate metabolic flux is emerging as an attractive strategy for bioprocess applications. We present the metabolic consequences of increasing NADH in the cytosol and the mitochondria of Saccharomyces cerevisiae. In a strain that was disabled in formate metabolism, we either overexpressed the native NAD(+)-dependent formate dehydrogenase in the ...

The hydrogenase and formate dehydrogenase levels in Syntrophobacter fumaroxidans and Methanospirillum hungatei were studied in syntrophic propionate-oxidizing cultures and compared to the levels in axenic cultures of both organisms. Cells grown syntrophically were separated from each other by Percoll gradient centrifugation. In S. fumaroxidans both formate dehydrogenase and hydrogenase levels w...

The current energy model based on fossil fuels is coming to an end due to the increase in global energy demand. Biofuels such as ethanol and butanol can be produced through the syngas fermentation by acetogenic bacteria. The present work hypothesizes that formate addition would positively impact kinetic parameters for growth and alcohol production in Clostridium ljungdahlii PETC and Clostridium...