H5000

Hexokinase from Saccharomyces cerevisiae

Type III, lyophilized powder, ≥25 units/mg protein (biuret)

• Synonym(s): ATP:D-Hexose-6-phosphotransferase, Hexokinase from yeast
• CAS Number: 9001-51-8
• UNSPSC Code: 12352204
• eCl@ss: 32160410
• EC Number: 232-611-5
• MDL number: MFCD00131321
• EC Number: 2.7.1.1 (BRENDA, IUBMB)
• Specific activity: ≥25 units/mg protein (biuret)

Properties

• type: Type III
• form: lyophilized powder
• specific activity: ≥25 units/mg protein (biuret)
• mol wt: dimer 110 kDa
• UniProt accession no.: P04806, P04807
• foreign activity: glucose-6-phosphate dehydrogenase and phosphoglucose isomerase ≤10%
• storage temp.: −20°C
• Gene Information: bakers yeast ... HXK1(850614), HXK2(852639)

Description

Biochem/physiol Actions

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)

Physical form

Lyophilized powder containing approx. 15% sodium citrate

Other Notes

One unit will phosphorylate 1.0 μmole of D-glucose per min at pH 7.6 at 25 °C, unless otherwise indicated below.

Safety Information

• Storage Class: 11 - Combustible Solids
• wgk: WGK 3
• flash_point_f: Not applicable
• flash_point_c: Not applicable
• ppe: Eyeshields, Gloves, type N95 (US)