Hexokinase

Hexokinase IVhexokinase-2
A hexokinase is an enzyme that phosphorylates hexoses (six-carbon sugars), forming hexose phosphate.wikipedia
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Enzyme

enzymologyenzymesenzymatic
A hexokinase is an enzyme that phosphorylates hexoses (six-carbon sugars), forming hexose phosphate.
For example, hexokinase (EC 2.7.1.1) is a transferase (EC 2) that adds a phosphate group (EC 2.7) to a hexose sugar, a molecule containing an alcohol group (EC 2.7.1).

Glucokinase

GCKMODY2
Hexokinases should not be confused with glucokinase, which is a specific isoform of hexokinase. The location of the phosphorylation on a subcellular level occurs when glucokinase translocates between the cytoplasm and nucleus of liver cells.
Glucokinase (GK) is a hexokinase isozyme, related homologously to at least three other hexokinases.

Glucose 6-phosphate

glucose-6-phosphateG6PD-glucose 6-phosphate
In most organisms, glucose is the most important substrate of hexokinases, and glucose-6-phosphate is the most important product.
This is catalyzed by the enzyme hexokinase in most cells, and, in higher animals, glucokinase in certain cells, most notably liver cells.

Glucose

dextroseD-glucose D -glucose
In most organisms, glucose is the most important substrate of hexokinases, and glucose-6-phosphate is the most important product.
In the other cell types, phosphorylation occurs through a hexokinase, whereupon glucose can no longer diffuse out of the cell.

Glycolysis

glycolyticglycolytic pathwayEmbden–Meyerhof pathway
Phosphorylation of a hexose such as glucose often limits it to a number of intracellular metabolic processes, such as glycolysis or glycogen synthesis.
The first step in glycolysis is phosphorylation of glucose by a family of enzymes called hexokinases to form glucose 6-phosphate (G6P).

Adenosine triphosphate

ATPadenosine triphosphate (ATP)adenosine 5'-triphosphate
They are categorized as actin fold proteins, sharing a common ATP binding site core that is surrounded by more variable sequences which determine substrate affinities and other properties.
In glycolysis, hexokinase is directly inhibited by its product, glucose-6-phosphate, and pyruvate kinase is inhibited by ATP itself.

Essential fructosuria

Fructosuria
In patients with essential fructosuria, metabolism of fructose by hexokinase to fructose-6-phosphate is the primary method of metabolizing dietary fructose; this pathway is not significant in normal individuals.
This defective degradation does not cause any clinical symptoms, fructose is either excreted unchanged in the urine or metabolized to fructose-6-phosphate by alternate pathways in the body, most commonly by hexokinase in adipose tissue and muscle.

Isozyme

isoenzymeisozymesisoenzymes
Several hexokinase isoforms or isozymes that provide different functions can occur in a single species.
An example of an isozyme is glucokinase, a variant of hexokinase which is not inhibited by glucose 6-phosphate.

Cell nucleus

nucleusnucleinuclear
The location of the phosphorylation on a subcellular level occurs when glucokinase translocates between the cytoplasm and nucleus of liver cells.
Hexokinase is an enzyme responsible for the first the step of glycolysis, forming glucose-6-phosphate from glucose.

Insulin

insulin geneINShuman insulin
In the beta cells of the pancreatic islets, it serves as a glucose sensor to control insulin release, and similarly controls glucagon release in the alpha cells.

HK3

hexokinase 3 (white cell)
Hexokinases phosphorylate glucose to produce glucose-6-phosphate (G6P), the first step in most glucose metabolism pathways.

HK2

hexokinase 2hexokinase II
Hexokinases phosphorylate glucose to produce glucose-6-phosphate (G6P), the first step in most glucose metabolism pathways.

HK1

hexokinase 1
Hexokinases phosphorylate glucose to produce glucose-6-phosphate (G6P), the first step in most glucose metabolism pathways.

Glucose 6-phosphatase

glucose-6-phosphataseglucose 6 phosphataseglycogen-6-phosphatase

Phosphorylation

phosphorylatedphosphorylatephosphorylates
A hexokinase is an enzyme that phosphorylates hexoses (six-carbon sugars), forming hexose phosphate. The location of the phosphorylation on a subcellular level occurs when glucokinase translocates between the cytoplasm and nucleus of liver cells.

Hexose

hexoses6-carbon sugaraldohexose
A hexokinase is an enzyme that phosphorylates hexoses (six-carbon sugars), forming hexose phosphate.

Sugar

sugarssugar tradesugar cube
A hexokinase is an enzyme that phosphorylates hexoses (six-carbon sugars), forming hexose phosphate.

Substrate (chemistry)

substratessubstratesubstrate specificity
In most organisms, glucose is the most important substrate of hexokinases, and glucose-6-phosphate is the most important product.

Gene

genesnumber of genesgene sequence
Genes that encode hexokinase have been discovered in every domain of life, and exist among a variety of species that range from bacteria, yeast, and plants to humans and other vertebrates.

Bacteria

bacteriumbacterialEubacteria
Genes that encode hexokinase have been discovered in every domain of life, and exist among a variety of species that range from bacteria, yeast, and plants to humans and other vertebrates.

Yeast

yeastsbrewer's yeastbudding yeast
Genes that encode hexokinase have been discovered in every domain of life, and exist among a variety of species that range from bacteria, yeast, and plants to humans and other vertebrates.

Plant

Plantaeplantsflora
Genes that encode hexokinase have been discovered in every domain of life, and exist among a variety of species that range from bacteria, yeast, and plants to humans and other vertebrates.

Vertebrate

Vertebratavertebratesvertebral
Genes that encode hexokinase have been discovered in every domain of life, and exist among a variety of species that range from bacteria, yeast, and plants to humans and other vertebrates.

Species

specificspecific epithetspecific name
Several hexokinase isoforms or isozymes that provide different functions can occur in a single species.

Glycogen

glycogen depositsglycogen (n)glycogen deposits
Phosphorylation of a hexose such as glucose often limits it to a number of intracellular metabolic processes, such as glycolysis or glycogen synthesis.