Acetogens are defined as anaerobic prokaryotes that use the acetyl-CoA pathway for the (a) reductive synthesis of the acetyl moiety of acetyl-CoA from CO2, (b) conservation of energy, and (c) assimilation of CO2 into biomass.
Acetogens utilize the acetyl-CoA “Wood–Ljungdahl” pathway as a terminal electron-accepting, energy-conserving, CO2-fixing process. The reductive synthesis of acetate from CO2 differentiates acetogens from organisms that synthesize acetate by other metabolic processes. Although the production of acetate as a sole reduced end product is the classic hallmark of acetogens, the production of acetate is not a part of the definition, because the acetogen might not form acetate in situ or when cultured in the laboratory.
KeywordsBiomass Cellulose Fermentation Lignin Superoxide
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