The biosynthesis of fructose has multiple point of origin: -Sucrose is metabolized by an invertase resulting in the release of B-D-fructofuranose and D-glucopyranose. D-glucopyranose is then phosphorylated through a ATP driven glucokinase resulting in the release of a hydrogen ion, ADP and D-glucopyranose 6-phosphate. The latter compound is then isomerized through a D-glucopyranose 6-phosphate isomerase resulting in the release of a B-D-fructofuranose 6-phosphate -Sucrose is metabolized by an invertase resulting in the release of B-D-fructofuranose and D-glucopyranose. B-D-fructofuranoseis phosphorylated through an ATP driven fructokinase resulting in the release of B-D-fructofuranose 6-phosphate. -D-sorbitol reacts with sorbitol dehydrogenase resulting in the release of keto-D-fructose.The latter compound reacts spontaneously in B-D-fructofuranose. The latter compound is then phosphorylated through a fructokinase resulting in the release of B-D-fructofuranose 6-phosphate -Sucrose 6-phosphate reacts with an invertase resulting in the release of B-D-fructofuranose and B-D-glucose 6-phosphate. The latter compound is then phosphorylated through a fructokinase resulting in the release of B-D-fructofuranose 6-phosphate The degradation of B-D-fructofuranose 6-phosphate starts with the phosphorylation of B-D-fructofuranose 6-phosphate through a 6-phosphofructo-2-kinase resulting in the release of B-D-fructose 2,6-bisphosphate that can be latter incorporated into glycolysis

Fructose Metabolism References