Glucokinase ( EC 2.7.1.2 ) is the fourth isotype of the enzyme hexokinase , which is mainly present in hepatocytes , as well as in pancreatic cells . Catalyzes the phosphorylation of hexatom sugars ( hexoses ), in particular D-glucose , D-mannose , D-fructose , D-glucosamine , sorbitol .
| Glucokinase | |
|---|---|
 | |
| Identifiers | |
| Cipher cf | 2.7.1.2 |
| CAS Number | 9001-36-9 |
| Enzyme bases | |
| Intenz | Intenz view |
| BRENDA | BRENDA entry |
| Expasy | NiceZyme view |
| Metacyc | metabolic pathway |
| Kegg | KEGG entry |
| PRIAM | profile |
| PDB structures | RCSB PDB PDBe PDBj PDBsum |
| Gene ontology | AmiGO • EGO |
| Search | |
| PMC | articles |
| PubMed | articles |
| NCBI | NCBI proteins |
| Cas | 9001-36-9 |
Glucokinase has a K m of the order of 10 mol mol / L and causes a rapid absorption of glucose from the blood in the liver during the absorption period . In this case, glucose enters hepatocytes via GLUT2- type transporters , the activity of which is not regulated by the level of insulin , but whose affinity for glucose is small (K m ≈ 10 mmol / L). Insulin affects glucose uptake by the liver only indirectly - it induces glucokinase synthesis in hepatocytes. Thus, glucokinase is designed to quickly transfer excess blood glucose that occurs after a meal to glycogen .
Reaction equation:
D-hexose + ATP → D-hexose-6-phosphate + ADP.