Cat No.
DIA-189
Description
β-galactosidase, also called beta-gal or β-gal, is a hydrolase enzyme that catalyzes the hydrolysis of β-galactosides into monosaccharides. Substrates of different β-galactosidases include ganglioside GM1, lactosylceramides, lactose, and various glycoproteins.
Abbr
GLB (E. coli)
Alias
β-gal; GLB
Species
Escherichia coli
Form
Freeze dried powder
Enzyme Commission Number
EC 3.2.1.23
Bio-activity
GradeⅡ 500U/mg-solid or more
Appearance
White amorphous powder, lyophilized.
Molecular Mass
540 kDa
pH Stability
pH 6.5-8.5 (25°C, 20hr)
Michaelis Constant
3.0×10??M (o-Nitrophenyl-?-D-galactoside), 6.7×10??M (p-Nitrophenyl-?-D-galactoside), 2.3×10??M (Phenyl-?-D-galactoside), 2.5×10?3M (Lactose)
Structure
The enzyme is composed of four identical subunits having a molecular weight of ca.135,000. The amino acid analysis indicates approximately 1,170 residues per subunit.
Isoelectric point
4.61
Specificity
The enzyme specifically hydrolyzes ?-D-galactosyl linkage
Optimum pH
7.0-7.5
Optimum temperature
50-55°C
Stabilizers
Mg??
Thermal stability
below 50°C (pH 7.3, 15min)
Stability
Stable at-20°C for at least 6 months
Inhibitors
p-Chloromercuribenzoate, lodoacetamide, heavy metal ions (Zn??, Fe???, Cd??, Cu??, Pb??, Ag?, Hg??), lonic detergents (SDS, DAC, etc.)
Applications
This enzyme is useful for structural investigation of carbohydrates, the determination of lactose (foodstuff analysis) and as an enzyme label for enzyme immunoassay.
Synonyms
β-galactosidase; beta-gal; β-gal; EC 3.2.1.23; lactase; β-lactosidase; maxilact; hydrolact; β-D-lactosidase; S 2107; lactozym; trilactase; β-D-galactanase; oryzatym; sumiklat; β-D-galactoside galactohydrolase
