<Tr> <Th> PubMed </Th> <Td> articles </Td> </Tr> <Tr> <Th> NCBI </Th> <Td> proteins </Td> </Tr> <P> Glucokinase (EC 2.7. 1.2) is an enzyme that facilitates phosphorylation of glucose to glucose - 6 - phosphate . Glucokinase occurs in cells in the liver and pancreas of humans and most other vertebrates . In each of these organs it plays an important role in the regulation of carbohydrate metabolism by acting as a glucose sensor, triggering shifts in metabolism or cell function in response to rising or falling levels of glucose, such as occur after a meal or when fasting . Mutagens of the gene for this enzyme can cause unusual forms of diabetes or hypoglycemia . </P> <P> Glucokinase (GK) is a hexokinase isozyme, related homologously to at least three other hexokinases . All of the hexokinases can mediate phosphorylation of glucose to glucose - 6 - phosphate (G6P), which is the first step of both glycogen synthesis and glycolysis . However, glucokinase is coded by a separate gene and its distinctive kinetic properties allow it to serve a different set of functions . Glucokinase has a lower affinity for glucose than the other hexokinases do, and its activity is localized to a few cell types, leaving the other three hexokinases as more important preparers of glucose for glycolysis and glycogen synthesis for most tissues and organs . Because of this reduced affinity, the activity of glucokinase, under usual physiological conditions, varies substantially according to the concentration of glucose . </P>

How does glucokinase act as a glucose sensor
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