Search results
Results from the WOW.Com Content Network
A hexokinase is an enzyme that irreversibly phosphorylates hexoses (six-carbon sugars), forming hexose phosphate. In most organisms, glucose is the most important substrate for hexokinases, and glucose-6-phosphate is the most important product. Hexokinase possesses the ability to transfer an inorganic phosphate group from ATP to a substrate.
Hexokinase II, also known as Hexokinase B and HK2, is an enzyme which in humans is encoded by the HK2 gene on chromosome 2. [5] [6] Hexokinases phosphorylate glucose to produce glucose 6-phosphate, the first step in most glucose metabolism pathways.
When ample glucose is available, glycogen synthesis proceeds at the periphery of the hepatocytes until the cells are replete with glycogen. Excess glucose is then increasingly converted into triglycerides for export and storage in adipose tissue. Glucokinase activity in the cytoplasm rises and falls with available glucose.
Hexokinase I, also known as hexokinase A and HK1, is an enzyme that in humans is encoded by the HK1 gene on chromosome 10. Hexokinases phosphorylate glucose to produce glucose-6-phosphate (G6P), the first step in most glucose metabolism pathways. This gene encodes a ubiquitous form of hexokinase which localizes to the outer membrane of ...
Hexokinase III, also known as hexokinase C, is an enzyme which in humans is encoded by the Hk3 gene on chromosome 5. [5] [6] Hexokinases phosphorylate glucose to produce glucose-6-phosphate, the first step in most glucose metabolism pathways. Similar to hexokinases I and II, this allosteric enzyme is inhibited by its product glucose-6-phosphate.
l-Glucose does not occur naturally in living organisms, but can be synthesized in the laboratory. l-Glucose is indistinguishable in taste from d-glucose, [1] but cannot be used by living organisms as a source of energy because it cannot be phosphorylated by hexokinase, the first enzyme in the glycolysis pathway.
When glucose has been converted into G6P by hexokinase or glucokinase, it can either be converted to glucose-1-phosphate (G1P) for conversion to glycogen, or it is alternatively converted by glycolysis to pyruvate, which enters the mitochondrion where it is converted into acetyl-CoA and then into citrate.
The glucokinase regulatory protein (GKRP) also known as glucokinase (hexokinase 4) regulator (GCKR) is a protein produced in hepatocytes (liver cells). GKRP binds and moves glucokinase (GK), thereby controlling both activity and intracellular location [1] [2] of this key enzyme of glucose metabolism. [3] GKRP is a 68 kD protein of 626 amino acids.