Catabolic enzymes of the acetogen Butyribacterium methylotrophicum grown on single-carbon substrates.

AUTOR(ES)

Kerby, R

RESUMO

When grown on formate, formate-CO, and methanol-CO, Butyribacterium methylotrophicum contained high levels of tetrahydrofolate (H4folate) and required enzymes, carbon monoxide dehydrogenase, formate dehydrogenase, and hydrogenase. The activities of methylene-H4folate reductase were comparable to other H4 folate activities (which ranged from 0.55 to 9.28 mumol/min per mg of protein) when measured by an improved procedure. The H4folate activities in formate-grown cells were twice those found in formate-CO-grown cells. This result correlated with a growth yield on formate that was one-half that on formate-CO. The stoichiometry of the formyl-H4folate synthetase reaction was 1 mol of ATP per 1 mol of formate. The methylene-H4folate dehydrogenase was NAD+ dependent. We conclude that B. methylotrophicum utilizes these enzymes in homoacetogenic catabolism.

Documentos Relacionados

• Single-carbon catabolism in acetogens: analysis of carbon flow in Acetobacterium woodii and Butyribacterium methylotrophicum by fermentation and 13C nuclear magnetic resonance measurement.
• Carbon monoxide metabolism of the methylotrophic acidogen Butyribacterium methylotrophicum.
• Glycosidases of the rumen anaerobic fungus Neocallimastix frontalis grown on cellulosic substrates.
• Cytochrome c. Observation of Numerous Single-Carbon Sites of the Reduced and Oxidized Species by Means of Natural-Abundance 13C Nuclear Magnetic Resonance Spectroscopy
• Formation and dissimilation of oxalacetate and pyruvate Pseudomonas citronellolis grown on noncarbohydrate substrates.