In anoxic environments such as swamps, rice fields and sludge digestors, syntrophic microbial communities are important for decomposition of organic matter to CO2 CH4 . The most difficult step is the fermentative degradation short-chain fatty acids propionate butyrate. Conversion these metabolites acetate, , formate hydrogen endergonic under standard conditions occurs only if methanogens keep concentrations intermediate products low. Butyrate pathways include oxidation steps comparably high...

In syntrophic conversion of butyrate to methane and CO2, is oxidized acetate by secondary fermenting bacteria such as Syntrophomonas wolfei in close cooperation with methanogenic partner organisms, e.g., Methanospirillum hungatei. This process involves an energetically unfavourable shift electrons from the level butyryl-CoA oxidation substantially lower redox potential proton and/or CO2 reduction, order transfer these via hydrogen formate. present study, all prominent membrane-bound soluble...

Lysine degradation has remained elusive in many organisms including Escherichia coli. Here we report catabolism of lysine to succinate E. coli involving glutarate and L-2-hydroxyglutarate as intermediates. We show that CsiD acts an α-ketoglutarate-dependent dioxygenase catalysing hydroxylation L-2-hydroxyglutarate. is found widespread bacteria. present crystal structures complex with glutarate, succinate, the inhibitor N-oxalyl-glycine, demonstrating strong discrimination between...

Sulfoquinovose (SQ, 6-deoxy-6-sulfoglucose) is produced by plants and other phototrophs its biodegradation a relevant component of the biogeochemical carbon sulfur cycles. SQ known to be degraded aerobic bacterial consortia in two tiers via C3-organosulfonates as transient intermediates CO2, water sulfate. In this study, we present first laboratory model for anaerobic degradation acetate hydrogen sulfide (H2S). For tier, SQ-degrading Escherichia coli K-12 was used. It catalyzes fermentation...

Thermacetogenium phaeum is a thermophilic strictly anaerobic bacterium oxidizing acetate to CO2 in syntrophic association with methanogenic partner. It can also grow pure culture, e.g., by fermentation of methanol acetate. The key enzymes homoacetate (Wood-Ljungdahl pathway) are used both oxidation and formation. obvious reversibility this pathway organism specific interest since operates close the energetic limitations microbial life. genome Th. organized on single circular chromosome has...

The platform chemicals n-caproate and iso-butyrate can be produced by anaerobic fermentation from agro-industrial residues in a process known as microbial chain elongation. Few lactate-consuming chain-elongating species have been isolated knowledge on their shared genetic features is still limited. Recently we three novel clostridial strains (BL-3, BL-4, BL-6) that convert lactate to iso-butyrate. Here, analyzed the background of lactate-based elongation these isolates other comparative...

We have previously isolated cDNA clones for the gip17 gene encoding cytosolic nucleoside diphosphate (NDP) kinase from Dictyostelium discoideum, and partial cDNAs guk, a second member of NDP family (Wallet, V., Mutzel, R., Troll, H., Barzu, O., Wurster, B., Veron, M., Lacombe, M. L. (1990) J. Natl. Cancer Inst. 80, 1199-1202). now characterize genomic DNA both genes, we show that guk defines nuclear-encoded mitochondrial kinase. Isolated D. discoideum mitochondria contain 3% total cellular...

Syntrophic mineralisation of benzene, as recently proposed for a sulphate-reducing enrichment culture, was tested in product inhibition experiments with acetate and hydrogen, both putative intermediates anaerobic benzene fermentation. Using [13C6]-benzene enabled tracking the sensitively by analysis 13CO2. In noninhibited cultures, hydrogen detected at partial pressures 2.4 × 10−6± 1.5 10−6 atm. Acetate concentrations 17 ± 2 μM. Spiking 0.1 atm produced transient inhibitory effect on 13CO2...

Growth of the anaerobic thermophile Thermacetogenium phaeum with methanol, ethanol, ethanolamine, and acetate was investigated in axenic cultures syntrophic Methanothermobacter thermautotrophicus. Microcompartment genes were identified T. genome, presence microcompartments confirmed by transmission electron microscopy proteome analysis. These expressed only during growth ethanolamine. Proteome data compared after all four substrates, activities key enzymes Wood-Ljungdahl pathway enzyme...

Oxidation of phosphite (HPO 3 2− ) to phosphate 4 releases electrons at a very low redox potential (E 0 ′ = −690 mV) which renders an excellent electron donor for microbial energy metabolism. To date, two pure cultures strictly anaerobic bacteria have been isolated that run their metabolism on the basis oxidation, Gram-negative Desulfotignum phosphitoxidans (DSM 13687) and Gram-positive Phosphitispora fastidiosa 112739). Here, we describe key enzyme dissimilatory oxidation in these bacteria....

Summary Six strains of novel bacteria were isolated from profundal sediment Lake Constance, a deep freshwater lake in Germany, by direct dilution the mineral agar medium containing background lawn hydrogen‐scavenging Methanospirillum hungatei as syntrophic partner. The numbers colony‐forming units obtained after incubation for more than 2 months same range those total bacterial counts determined DAPI staining (up to 10 8 cells per millilitre) suggesting that these organisms dominant members...

Methanogenic oxidation of butyrate to acetate requires a tight cooperation between the syntrophically fermenting Syntrophomonas wolfei and methanogen Methanospirillum hungatei, reversed electron transport system in S. was postulated shift electrons from butyryl coenzyme A (butyryl-CoA) redox potential NADH for H(2) generation. The metabolic activity butyrate-oxidizing cells measured via production formazan butyrate, with 2,3,5-triphenyltetrazolium chloride as acceptor. This inhibited by...

Pelobacter carbinolicus and P. acetylenicus oxidize ethanol in syntrophic cooperation with methanogens. Cocultures Methanospirillum hungatei served as model systems for the elucidation of oxidation previously done lost “Methanobacillus omelianskii” coculture. During growth on ethanol, both species exhibited NAD+-dependent alcohol dehydrogenase activity. Two different acetaldehyde-oxidizing activities were found: a benzyl viologen-reducing enzyme forming acetate, NAD+-reducing acetyl-CoA....

A novel strictly anaerobic, mesophilic bacterium was enriched and isolated with gluconate as sole substrate from a methanogenic sludge collected biogas reactor. Cells of strain GluBS11T stained Gram-positive were non-motile, straight rods, measuring 3.0-4.5 × 0.8-1.2 μm. The temperature range for growth 15-37 °C, optimal at 30 the pH 6.5-8.5, 7, generation time under conditions 60 min. API Rapid 32A reactions positive α-galactosidase, α-glucosidase β-glucosidase negative catalase oxidase....

The sulfate-reducing bacterium Desulfatiglans anilini can grow with phenol as sole source of carbon and energy under strictly anaerobic, conditions. In the nitrate-reducing Thauera aromatica, enzymes involved in degradation have been well elucidated, whereas anaerobic pathway by D. was not studied detail yet. identification genes coding for phenylphosphate synthase (encoded pps genes) carboxylase ppc genome anilini, analysis transcription translation pps-ppc genes, measurement activity...

A new strictly anaerobic bacterium, strain DYL19T, was enriched and isolated with phosphite as the sole electron donor CO2 a single carbon source acceptor from sewage sludge sampled at treatment plant in Constance, Germany. It is Gram-positive, spore-forming, slightly curved, rod-shaped bacterium which oxidizes to phosphate while reducing biomass small amounts of acetate. Optimal growth observed 30 °C, pH 7.2, doubling time 3 days. Beyond phosphite, no further inorganic or organic can be...

AME Aquatic Microbial Ecology Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsSpecials 47:83-90 (2007) - doi:10.3354/ame047083 Degradation of gallic acid and hydrolysable polyphenols is constitutively activated in freshwater plant-associated bacterium Matsuebacter sp. FB25 Nicolai Müller1,2, Melanie Hempel1, Bodo Philipp2, Elisabeth M. Gross1,* 1Limnology, Department Biology, University Konstanz, PO Box...

The thermophilic acetogen Thermacetogenium phaeum uses the Wood-Ljungdahl pathway (WLP) in both directions, either for production of acetate from various compounds or oxidation syntrophic cooperation with methanogens. In this study, energy-conserving enzyme systems T. were investigated metabolic directions. A gene cluster containing a membrane-bound periplasmically oriented formate dehydrogenase directly adjacent to putative menaquinone synthesis genes was identified genome. protein products...

Uptake of bumetanide into rat liver cells was investigated using isolated hepatocytes and primary cell cultures. The kinetics [3H]-bumetanide uptake revealed two saturable components in addition to an unsaturable component. Saturable consists a high-affinity, sodium-dependent low-affinity transport system. Bumetanide is energy dependent temperature sensitive. At low temperatures, due diffusion with permeability coefficient 1.16 x 10(-6) cm/s. In cultures, decreases rapidly over 3 days....

Growth of biodiesel industries resulted in increased coproduction crude glycerol which is therefore becoming a waste product instead valuable 'coproduct'. Glycerol can be used for the production chemicals, e.g. biofuels, to reduce disposal. In this study, novel bacterial strain described converts mainly ethanol and hydrogen with very little amounts acetate, formate 1,2-propanediol as coproducts. The bacterium offers certain advantages over previously studied glycerol-fermenting...