Methane-producing bacteria

Methane production [CO2 + H2 (or simple organic compound such as acetate) - CH4 + H2O] Methane-producing bacteria... 

The methane-producing bacteria that derive their energy from the oxidation of simple organic compounds such as methanol and acetate, release large quantities of methane. They... 

Reactive Orange 96 Anaerobic culture of sulfate-reducing bacteria, methanogens, and fermentative bacteria Sulfate-reducing bacteria removed 95% of the dye in 40 h. Methane producing bacteria did not contribute in dye removal. Fermentative bacteria could remove only 30% of the dye in 90 h [186]... 

Seeding. This is a component of the start-up practice and consists of the addition of actively digesting material to a newly operating digester. The addition ensures that a culture of methane-producing bacteria is present for start-up. 

This strain uses the carbon-chlorine bond as an electron acceptor and molecular hydrogen as its source of electrons. A number of other anaerobic microorganisms, particularly methane-producing bacteria, also use hydrogen as an electron source, but this bacterium uses it at a lower concentration than most of its competitors. 

One conclusion from these comparisons is that the methane-producing bacteria, the methanogens,24 are only distantly related to most other bacteria. Methano-... 

Much interest has also been expressed in tetra-azamacrocyclic compounds, due to their role in the natural reduction of C02 to CH4 by a nickel tetrapyrrole coenzyme found in methane-producing bacteria. Tinnemans et al. used Co(II) tetra-azamacrocyclic complexes with [Ru(bpy)3]2+ as the photosensitizer and ascorbic acid as the sacrificial electron donor in aqueous C02-saturated solutions at acidic pH [33]. Whilst the TON for the total observed products of CO and H2 exceeded 500, they were formed in a ratio of 0.27 1, respectively. 

Gunnarsson, L.A.H., and Ronnow, P.H. (1982) Inter-relationships between sulfate reducing and methane producing bacteria in coastal sediments with intense sulfide production. Mar. Biol. 69, 121-128. 

Different groups of microorganisms participate in this anaerobic conversion. First, extracellular enzymes of hydrolytic bacteria liquefy the polymenic and insoluble substances. The produced monomers are then further degraded by acid-producing bacteria to acetic acid, H2, C02 etc. These metabolites are the substrate for methane-producing bacteria. The end product, a gas mixture of 70 % methane and... 

H.A. Barker, S. Ruben and M.D. Kamen, The Reduction of Radioactive Carbon Dioxide by Methane-Producing Bacteria, Proceedings (f the National Academy of Scierwes... 

The fermentation of carbohydrates and protein are each no doubt mediated by more than one species of bacteria, and so the assumption that this occurs in a single step is a significant simplification. However, the fermentation of hydrogen and the various fatty acids by independent species of methane producing bacteria appears to be quite realistic. 

Methane-producing bacteria obtain energy by reducing CO2 with molecular hydrogen ... 

Cappenberg, T.E., 1974a. Interrelations between sulfate-reducing and methane-producing bacteria in bottom deposits of a fresh water lake. I. Field observations. Antonie van Leeuwenhoek J. Microbiol. Serol., 40 285—295. 

FIGURE 4.8 The tetrapyrrole biosynthetic pathways. Chelatases selectively insert Fe " " to form haem, to form chlorophyll, Co to form cobalamine, and, in methane-producing bacteria, Ni " " to form coenzyme Frso-... 

Methanogens (methane-producing bacteria) oxidize hydrogen gas (H2) with carbon dioxide (C02) to produce methane (CH4) (Fig. 1.15). Some methanogens utilize... 

The methane-producing bacteria derive their energy from the oxidation of simple organic corn-pounds such as methanol and acetate, or from molecular hydrogen. Methane is the reduced product of their metabolism. These are among the most strictly anaerobic organisms. They are responsible for swamp gas (methane) production in the... 

As sulphate has been found to be present to deep depths in the mangrove sediments examined so far (e.g. Holmer etal., 1994 Alongi etal., 1998), methane production is not considered to be an important mineralization process in mangrove forests. Methane-producing bacteria are able to compete only with sulphate reducers for electron donors at low sulphate concentrations (<200 pM), and such low concentrations have not been measured at depths of 30-50 cm examined so far. The sulphate concentration may still be as high as 8mM at these depths (Holmer etal., 1994 Alongi etal., 1998). 

Methylcobalamin has an extensive chemistry, some of which is doubtless involved in the metabolism of methane-producing bacteria, and it has been shown that it transfers CH3 groups to Hg11, TIIU, Pt11 and Au1.26... 

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