Question

How does glucose convert pyruvate?

Answer 1

Conversion of glucose to pyruvate:

1. Glycolysis is the method of the breakdown of glucose into pyruvate.
2. In this method, the glucose molecule undergoes partial oxidation and forms 2 molecules of pyruvate and a pair of ATP.
3. It happens inside the cytoplasm of the cell.

Following are the steps of the glycolysis:

1. Glucose gets phosphorylated to glucose-6-phosphate by using two ATP molecules in the presence of the enzyme hexokinase.
2. Glucose-6-phosphate then isomerizes to provide fructose-6-phosphate.
3. Fructose 6-phosphate is converted into fructose 1, 6-bisphosphate using magnesium as a cofactor in the presence of phosphohexokinase enzyme.
4. The enzyme Aldolase breaks fructose 1, 6-bisphosphate into two sugars that are isomers of each other.
5. These two sugars are dihydroxyacetone phosphate (DHAP) and glyceraldehyde 3-phosphate (GAP).
6. The enzyme triphosphate isomerase rapidly interconverts the molecules dihydroxyacetone phosphate (DHAP) and glyceraldehyde 3-phosphate (GAP).
7. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) dehydrogenates and adds an inorganic phosphate to glyceraldehyde 3-phosphate, producing 1, 3-bisphosphoglycerate.
8. Two molecules of 1, 3-bisphosphoglycerate react with 2 ADP to form 2 molecules of 3-phosphoglycerate and 2 ATP.
9. 3-phosphoglycerate is now isomerised into 2-phosphoglycerate in the presence of phosphoglyceromutase enzyme.
10. A molecule of water is removed from 2-phosphoglycerate to form 2-phosphoenol pyruvic acid (2-PEPA) by an enzyme named enolase.
11. In the last step, 2-phosphoenol pyruvic acid (2-PEPA) reacts with 2 ADP molecules to produce 2 molecules of pyruvic acid and ATP in the presence of the pyruvickinase enzyme.