second stage of glycolysis

12
(the energy producing stage(

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Page 1: Second stage of Glycolysis

(the energy producing stage(

Page 2: Second stage of Glycolysis

a) The 2 molecules of glyceroaldehyde-3-

phosphate are converted into pyruvate (aerobic

glycolysis) or lactate (anaerobic glycolysis).

b) These steps produce ATP molecules (energy

production).

Page 3: Second stage of Glycolysis

the aldehyde group of glyceraldehyde-3-PO4 is oxidized to a carboxyl group and esterified with inorganic phosphate to form the high-ehergy compound 1,3-biphosphoglycerate. The reaction is catalyzed by glyceraldehyde-3-PO4

dehydrogenase, during w/c NAD+ is reduced to NADH

Page 4: Second stage of Glycolysis

Phosphoglycerate kinase catalyzes the phosphorylation of ADP by the high-energy compound 1,3-biphosphoglycerate to form ATP and 3-phosphoglycerate.

Page 5: Second stage of Glycolysis

Phosphoglyceromutase catalyzes the rearrangement of 3-phosphoglycerate into 2-phosphoglycerate

Page 6: Second stage of Glycolysis

Enolase then catalyzes the dehydration of 2-phosphoglycerate to yield the phosphorylated enol form of pyruvate, phosphoenolpyruvate, the second high-energy compound produced by the glycolytic process.

Page 7: Second stage of Glycolysis

ADP is then enzymatically phosphorylated by pyruvate kinase, and the enol form of pyruvate rapidly rearranges nonenzymatically to the keto form of pyruvate

Page 8: Second stage of Glycolysis

NAD+ is regenerated by the reduction of pyruvate to lactate catalyzed by lactic dehydrogenase.

Page 9: Second stage of Glycolysis
Page 10: Second stage of Glycolysis

is a process that generates  NADPH and pentoses.

There are two distinct phases in the pathway. -the first is the oxidative phase, in which NADPH is generated, and the second is the non-oxidative synthesis of 5-carbon sugars.

This pathway is an alternative to glycolysis. 

its primary role is anabolic (constructive metabolism) rather than catabolic (destructive metabolism)

Page 11: Second stage of Glycolysis
Page 12: Second stage of Glycolysis

After glycolysis, the catabolism of glucose continues with the entry of pyruvate into the mitochondria. There, the pyruvate is oxidatively transformed into acetyl-s-CoA, w/c is subsequently oxidized in the citric acid cycle.