Pyruvate fermentation by Clostridium acetobutylicum.

Clostridium acetobutylicum ATCC 824 using pyruvate as the sole carbon source produced mainly acetate and butyrate as end products of fermentation. Acetate and butyrate kinase activities were higher in cells growing in the presence of pyruvate than glucose, whereas the level of the acetoacetate decarboxylase, an enzyme involved in solvent formation, was lower. Similar activities of glyceraldehyde-3-phosphate dehydrogenase were found in cells grown in pyruvate and glucose mediums. The transfer of C. acetobutylicum from pyruvate to glucose medium suggested that pyruvate represses the "solventogenesis."