Lactate formation from fructose or C1 compounds in the acetogen Acetobacterium woodii by metabolic engineering.

Anaerobic, acetogenic bacteria are promising biocatalysts for a sustainable bioeconomy since they capture and convert carbon dioxide to acetic acid. Hydrogen is an intermediate in acetate formation from organic as well as C1 substrates. Here, we analyzed mutants of the model acetogen Acetobacterium woodii in which either one of the two hydrogenases or both together were genetically deleted.

Reprogramming the metabolism of an acetogenic bacterium to homoformatogenesis.

Methyl groups are abundant in anoxic environments and their utilization as carbon and energy sources by microorganisms involves oxidation of the methyl groups to CO, followed by transfer of the electrons to an acceptor. In acetogenic bacteria, the electron acceptor is CO that is reduced to enzyme bound carbon monoxide, the precursor of the carboxyl group in acetate. Here, we describe the generation of a mutant of the acetogen Acetobacterium woodii in which the last step in methyl group oxidation, formate oxidation to CO catalyzed by the HDCR enzyme, has been genetically deleted.