gliceraldehid3foszfátdehidrogenáz

Gliceraldehid3, also known as glyceraldehyde 3-phosphate (G3P), is a crucial intermediate in both glycolysis and gluconeogenesis, fundamental metabolic pathways in living organisms. It is a three-carbon sugar phosphate molecule. In glycolysis, the breakdown of glucose to generate energy, G3P is formed from fructose-1,6-bisphosphate through the action of the enzyme aldolase. This step is reversible. Following its formation, G3P is then further oxidized and phosphorylated to produce 1,3-bisphosphoglycerate, a high-energy phosphate compound that will eventually lead to the production of ATP.

In gluconeogenesis, the synthesis of glucose from non-carbohydrate precursors, G3P plays a similar central role but in the reverse direction. It is formed from dihydroxyacetone phosphate (DHAP), another three-carbon sugar phosphate, catalyzed by triose phosphate isomerase. G3P is then converted to fructose-1,6-bisphosphate, which eventually leads to the formation of glucose. This interconversion between G3P and DHAP is essential for the cyclical nature of these pathways. The precise regulation of G3P levels is vital for maintaining cellular energy homeostasis and providing building blocks for biosynthesis.