Glucokinase
Glucokinase is an enzyme that phosphorylates glucose to become glucose-6-phosphate. It is an isozyme of hexokinase (hexokinase IV) that is present in hepatocytes. Compared to the other forms of hexokinase, glucokinase has a low affinity for glucose. This means that when glucose levels in the body are low, glucose isn't phosphorylated to become glucose-6-phosphate, and it goes to other tissues that have a greater need for the glucose. Furthermore, glucokinase is not inhibited by the product glucose-6-phosphate. This allows the enzyme to continually phosphorylate glucose, even when the concentration of glucose-6-phosphate is very high[1].
References
- ↑ Lehninger, A. L. Nelson, D. L. Cox, M. M. (2000) Principles of Biochemistry, 6th edition, New York: Worth Publishers. Chapter 15, page 578.
- ↑ RCSB Protein Data Bank. 1V4T: Crystal Structure of Human GLucokinase Structure Summary Page. 2011. [cited: 5/12/2016] Available from: http://www.rcsb.org/pdb/explore.do?structureId=1v4t