Abstract: | The NADH and NADPH-ferredoxin oxidoreductase have been studied in Clostridium acetobutylicum. Acetyl-CoA is an obligatory activator of NADH-ferredoxin reductase activity and NADH a competitive inhibitor of ferredoxin-NAD+ reductase activity. These regulations are the same when C. acetoburylicum moves from 'butylic-type metabolism' to 'butyric-type metabolism'; this demonstrates that NADH-ferredoxin oxidoreductase cna, through its reversible action, meet the very different cell needs imposed by these two types of culture. The physiological function of the clostridial NADPH-ferredoxin oxidoreductase was anabolic as it has been with other clostridia. |