Hexokinase (HK)

Hexokinase is an enzyme that phosphorylates hexoses, forming hexose-6-phosphate. In most tissues, glucose is the most important substrate, and the product is glucose-6-phosphate (G6P), the first step in glycolysis. There are four main mammalian isoforms (HK-I, HK-II, HK-III, and glucokinase/HK-IV), each with distinct tissue distribution, regulatory properties, and roles in glucose metabolism and insulin secretion. Dysregulation of hexokinase activity is implicated in various diseases, including cancer and diabetes.

Other names

Hexokinase IHexokinase IIHexokinase IIIGlucokinaseHK-IHK-IIHK-IIIHK-IV

Catalyzes the phosphorylation of hexoses (primarily glucose) to glucose-6-phosphate, initiating glycolysis. Glucokinase acts as a glucose sensor in pancreatic beta cells, regulating insulin secretion based on blood glucose levels.