Dihydroxyacetone phosphate (DHAP, also glycerone phosphate in older texts) is the anion with the formula HOCH2C(O)CH2OPO32-. This anion is involved in many metabolic pathways, including the Calvin cycle in plants and glycolysis.[1] [2] It is the phosphate ester of dihydroxyacetone.
Dihydroxyacetone phosphate lies in the glycolysis metabolic pathway, and is one of the two products of breakdown of fructose 1,6-bisphosphate, along with glyceraldehyde 3-phosphate. It is rapidly and reversibly isomerised to glyceraldehyde 3-phosphate.
The numbering of the carbon atoms indicates the fate of the carbons according to their position in fructose 6-phosphate.
In the Calvin cycle, DHAP is one of the products of the sixfold reduction of 1,3-bisphosphoglycerate by NADPH. It is also used in the synthesis of sedoheptulose 1,7-bisphosphate and fructose 1,6-bisphosphate, both of which are used to reform ribulose 5-phosphate, the 'key' carbohydrate of the Calvin cycle.
DHAP is also the product of the dehydrogenation of L-glycerol-3-phosphate, which is part of the entry of glycerol (sourced from triglycerides) into the glycolytic pathway. Conversely, reduction of glycolysis-derived DHAP to L-glycerol-3-phosphate provides adipose cells with the activated glycerol backbone they require to synthesize new triglycerides. Both reactions are catalyzed by the enzyme glycerol 3-phosphate dehydrogenase with NAD+/NADH as cofactor.
DHAP also has a role in the ether-lipid biosynthesis process in the protozoan parasite Leishmania mexicana.
DHAP is a precursor to 2-oxopropanal. This conversion is the basis of a potential biotechnological route to the commodity chemical 1,2-propanediol.