glucose!2 lactate [X] The pyruvate formed is reduced to lactate by the action of lactate dehydrogenase, which catalyses a stereospecific reduction to either l- ord-lactate. The ATP yield is 2mol permolglucose.Heterofermentativebacteriaaredevoidof aldolase but contain phosphoketolase instead. Glucose 6phosphate is oxidized to 6-phosphogluconate and then decarboxylated to ribulose 5-phosphate. After epimerization the xylulose 5-phosphate is split by phosphoketolase to acetyl phosphate and glyceraldehyde 3-phosphate. To maintain a proper redox balance acetyl-CoA derived from acetyl phosphate is reduced to ethanol, and the glyceraldehyde 3-phosphate is converted to lactate. The overall reaction