Hexokinase is the first enzyme in the glycolytic pathway, catalyzing the transfer of a phosphoryl group from ATP to glucose to form glucose-6-phosphate and ADP. In vertebrates there are four major glucose-phosphorylating isoenzymes, designated hexokinase I, II, III, and IV This enzyme is found in most cells, but there is tissue specificity for the particular type of hexokinase. Hexokinase 2 is found in the skeletal muscle and includes hydrophobic N-terminal sequence capable of targeting the hexokinase to mitochondria. It also constitutes the principal regulated isoform in many other cell types and is increased in many cancers. Although found in NIDDM patients, genetic variations of HK 2 do not contribute to the disease. MW: 104.1 kDa. Purit