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.
KeywordsAnammox Bacterium Terminal Electron Acceptor Methanosarcina Acetivorans Reductive Synthesis Reductive Tricarboxylic Acid
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