second stage of glycolysis
TRANSCRIPT
(the energy producing stage(
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).
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
Phosphoglycerate kinase catalyzes the phosphorylation of ADP by the high-energy compound 1,3-biphosphoglycerate to form ATP and 3-phosphoglycerate.
Phosphoglyceromutase catalyzes the rearrangement of 3-phosphoglycerate into 2-phosphoglycerate
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.
ADP is then enzymatically phosphorylated by pyruvate kinase, and the enol form of pyruvate rapidly rearranges nonenzymatically to the keto form of pyruvate
NAD+ is regenerated by the reduction of pyruvate to lactate catalyzed by lactic dehydrogenase.
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)
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.