Question

What are the enzymes leading from GAP to pyruvate?

Answer 1

The enzymes that convert glyceraldehyde-3-phosphate (GAP) to pyruvate in glycolysis are glyceraldehyde-3-phosphate dehydrogenase, phosphoglycerate kinase, phosphoglycerate mutase, enolase, and pyruvate kinase.

Step-by-step explanation:

The enzymes leading from glyceraldehyde-3-phosphate (GAP) to pyruvate form part of the glycolytic pathway. The order of enzymatic reactions after GAP includes:

1. Glyceraldehyde-3-phosphate dehydrogenase: Converts GAP into 1,3-bisphosphoglycerate (BPG).
2. Phosphoglycerate kinase: Catalyzes the transfer of a phosphate from 1,3-BPG to ADP, forming ATP and 3-phosphoglycerate (3-PG).
3. Phosphoglycerate mutase: Converts 3-PG into 2-phosphoglycerate (2-PG).
4. Enolase: Dehydrates 2-PG to form phosphoenolpyruvate (PEP).
5. Pyruvate kinase: Catalyzes the transformation of PEP into pyruvate, producing a second ATP molecule by substrate-level phosphorylation.

These enzymes, especially pyruvate kinase, not only convert intermediates into pyruvate but are also regulated by energy needs of the cell. Pyruvate kinase regulation is linked to allosteric effects and phosphorylation, enabling the cell to modulate glycolysis based on its metabolic conditions.