Glycolysis

Metabolic Rx Many metabolic enzymes need coenzymes to function Common coenzymes: NAD, FAD, Coenzyme A, ATP These are nucleotide molecules accept/deliver electrons for redox reactions accept/delivers phosphates to generate ATP

NAD – Nicotinamide Adenine Dinucleotide

ATP – Adenosine Triphosphate

ATP Energy currency of the cell Energy is stored between negatively charged phosphates Rechargeable battery ADP + P → ATP

Coupled Rx Writing in Metabolism Dehydrogenase Enzyme Alcohol Aldehyde Substrate is oxidized NAD NADH Coenzyme is reduced

Glycolysis Pathway of 10 interconnected enzyme Rx Initial substrate: glucose Final product: pyruvate Most ancient metabolic pathway, evolved before O2 levels were high and therefore…. does not need O2, does not produce CO2 Takes place in the cytosol of cells has an energy investing phase (activation E) and energy yielding phase

Energy Summary of Glycolysis Per glucose molecule: Energy investing phase: -2 ATP invested/1 glucose Energy yielding phase: +4ATP Net yield +2 ATP Low net yield: only 2 mole ATP/1 mole glucose!!!

Net Rx of Glycolysis 1 Glucose + 2 ATP + 2ADP + 2P + 2NAD → 2 Pyruvate + 4 ATP + 2NADH + 2H2O

Warm-up Methandiol Methanoic Acid Rewrite the Rx with molecular structures Rewrite the Rx and add NAD/NADH coupled coenzyme arrow Rewrite the Rx as a Redox Rx (integrate the coupled arrow into the Rx)

Glycolysis Crashcourse Overview respiration