H4502

Hexokinase from Saccharomyces cerevisiae

Type F-300, lyophilized powder, ≥130 units/mg protein (biuret)

• Synonyme(s) : Hexokinase D, Hexokinasetype IV, ATP:D-Hexose-6-phosphotransferase, Hexokinase from yeast
• Numéro CAS: 9001-51-8
• Numéro de classification (Commission des enzymes): 2.7.1.1 (BRENDA, IUBMB)
• Numéro CE : 232-611-5
• Numéro MDL: MFCD00131321
• Code UNSPSC : 12352204
• eCl@ss : 32160410
• Nomenclature NACRES : NA.54

Propriétés

• Source biologique: Saccharomyces cerevisiae
• Niveau de qualité: 200
• Type: Type F-300
• Forme: lyophilized powder
• Activité spécifique: ≥130 units/mg protein (biuret)
• Poids mol.: 110 kDa
• Produit purifié par: crystallization
• Conditions de stockage: (Keep container tightly closed in a dry and well-ventilated place)
• Couleur: white
• Traces d'anions: sulfate (SO₄^2-): free
• Numéro d'accès UniProt: P04806; P04807
• Activité étrangère: ATPase, myokinase, glucose-6-phosphate dehydrogenase, 6-phosphogluconic dehydrogenase and phosphoglucose isomerase ≤0.01%
• Température de stockage: −20°C
• Informations sur le gène: bakers yeast ... HXK1(850614) , HXK2(852639)

Description

Description générale

Research area: Cell Signaling

The hexokinase 1 (HXK1) gene is mapped to the Saccharomyces cerevisiae chromosome VI. HXK1 is ubiquitously expressed in mammalian tissues and is abundant in the brain, erythrocytes, lymphocytes, and fibroblasts.

Application

Hexokinase has been used:

• for digesting glucose for measuring glucose content in the root and stem samples of Quercus velutina
• to treat ADP (adenosine diphosphate) solution along with D-glucose to remove the contaminating ATP (adenosine triphosphate)
• in 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid buffer (pH 7.5) for ADP-[13CU]glucose synthesis

Actions biochimiques/physiologiques

Catalyzes the phosphorylation of D-hexose sugars at the C6 position utilizing ATP as a phosphate source.

The rate of phosphorylation varies with different hexoses (pH 7.5, 30 °C).
D-fructose K_M: 0.33 mM
D-glucose K_M: 0.12 mM
D-mannose K_M: 0.05 mM

Yeast hexokinase exists as two similar isoforms, PI and PII (A and B), with isoelectric points of 5.25 and 4, respectively.

Molecular Weight: ~ 54 kDa (monomer)
~110 kDa (dimer)
Optimal pH: 7.5 to 9.0
Extinction Coefficient: E^1% = 8.85 (PI) and 9.47 (PII) at 280 nm

Activators: Hexokinase requires Mg²⁺ ions (K_M = 2.6 mM) for activity. Hexokinase is activated by catecholamines and related compounds.

Inhibitors: sorbose-1-phosphate, polyphosphates, 6-deoxy-6-fluoroglucose, 2-C-hydroxy-methylglucose, xylose, lyxose, and thiol reactive compounds (Hg²⁺ and 4-chloromercuribenzoate)

Hexokinase catalyzes the rate-limiting first step of glycolysis, which involves the phosphorylation of glucose.

Qualité

A mixture of isoenzymes.

Définition de l'unité

One unit will phosphorylate 1.0 μmole of D-glucose per min at pH 7.6 at 25 °C.

Forme physique

Lyophilized powder containing approx. 15% sodium citrate

Reconstitution

Reconstitute with water or citrate buffer, pH 7.0. Studies have shown excellent stability during repeated freezing and thawing over a period of at least 30 days.

Informations sur la sécurité

• Code de la classe de stockage: 11 - Combustible Solids
• Classe de danger pour l'eau (WGK): WGK 3
• Point d'éclair (°F): Not applicable
• Point d'éclair (°C): Not applicable
• Équipement de protection individuelle: Eyeshields, Gloves, type N95 (US)