Pyruvate
Pyruvate has three different fates. Under aerobic conditions, pyruvate enters mitochondriaand is converted to acetyl CoA. The acetyl CoA enters thecitric acid cycle. Reducing equivalents produce of the citric acid cycle enter the electrontransport chain where oxidation is completed and ATP is synthesized. A second fate ofpyruvate is conversion to lactate. This takes place in anaerobic microorganisms and inour own bodies when glycolysis occurs faster than the oxygen dependent citric acidcycle and electron transport chain can operate. Some microorganisms convert pyruvateto ethanol, the third fate of pyruvate. In each of these three processes, NAD' isregenerated so that glycolysis can continue. We shall learn in greater details about thefirst two fates of pyruvate now, starting with formation of lactate.