Woods-Ljungdahl pathway

Strong evidence that the methanotrophic bacteria use the Wood-Ljungdahl pathway in reverse for the conversion of acetate to methane. ... 

C. thermoaceticum contains a gene cluster encoding at least five genes in the Wood-Ljungdahl pathway (130). These genes are apparently not regulated by CO. The CODH activity does increase about fourfold when methanogenic cells are exposed to CO (131). There is... 

Figure 15.6 The Wood-Ljungdahl pathway. One molecule of C02 (blue) is converted to formate and then reduced to a methyl group, which is then transferred to the corrinoid-iron-sulphur protein CFeSP. CFeSP transfers the methyl group to the A-cluster of the bifunctional CODH/ACS. The other molecule of C02 (red) is reduced to CO by the C-cluster of the CODH subunit. The CO is then transferred to the A-cluster through a long channel, some 70 A long, where with the methyl group and CoA it forms acetylCoA. (From Drennan et al., 2004. With kind permission of Springer Science and Business Media.)...

Drake HL. 1994. Acetogenesis, acetogenic bacteria, and the acetyl-CoA Wood/ Ljungdahl pathway past and current perspectives. In Drake HL, editor. Acetogenesis. New York Chapman Hall. 

The Reductive Acetyl-CoA Pathway (Wood-Ljungdahl Pathway)... 

Ragsdale, S. W., 1997,The Eastern and Western branches of the Wood/Ljungdahl pathway how the East and West were won, BioFactors 9 ln9. 

Conceptually, the simplest way to synthesize an organic molecule is to construct it one carbon at a time (Ragsdale and Pierce, 2008). The Woods—Ljungdahl pathway (Figure 15.3) does just that, synthesising acetyl-CoA from CO2. Carbon monoxide dehydrogenase, CODH and acetyl-CoA synthase, ACS are responsible for the reduction of CO2 to CO and the subsequent formation of acetyl-CoA (Drennan et al., 2004). CODH/ACS... 

FIGURE 15.3 The Wood—Ljungdahl pathway. H2 is used in a general sense to designate the requirement for two electrons and two protons in the reaction. (From Ragsdale Pierce, 2008. Copyright 2008 with permission from Elsevier.)... 

Ragsdale, S. W., Pierce, E. (2008). Acetogenesis and the Wood-Ljungdahl pathway of CO(2) fixation. Biochimica et Biophysica Acta, 1784, 1873-1898. 

For acetogens, such as the ones identified for producer gas fermentation, ethanol synthesis is reported to follow the Wood-Ljungdahl pathway. The overall stoichiometry for the formation of ethanol (C2H5OH) from CO, CO2, and H2 is... 

The bifunctional carbon monoxide dehydrogenase (CODH)/acetyl-CoA synthase enzyme is a key enzyme involved in the Wood-Ljungdahl pathway of carbon fixation that operates in anaerobic bacteria. As such, it is a major player in the global carbon cycle. The CODH component of the enzyme catalyzes the reversible reduction of CO2 to CO (Equation (15)), which is then channeled to the ACS active site where it reacts with CoA and a methyl group provided by the corrinoid iron-sulfur protein (CFeSP) to form acetyl-CoA 30 (Equation (16)). 

This acetyl-CoA pathway (or Wood-Ljungdahl pathway) involves reduction by H2 of one of the two molecules of CO2 to the methyl group of methyl-tetrahydromethanopterin in methanogens and of methyltetra-hydrofolate in acetogens. The pathway utilized by methanogens is illustrated in Fig. 15-22. ... 

The methanogens used the Wood-Ljungdahl pathway to turn the air into sugars and carbon chains, making methane waste. Other microbes ate the methane, cracking its bonds open to get at the electrons inside, producing carbon dioxide and... 

The Wood-Ljungdahl pathway may have been the first metabolism. .. R. Braakman and E. Smith. The emergence and early evolution of biological carbon-fixation. PLoS ComputBiol. 8(4), p. el002455. DOl 10.1371/journal.pcbi.l002455. 

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