β-Galactosidase from Escherichia coli Grade VIII, lyophilized powder, ≥500 units/mg protein Sigma G5635
По запросу
- Производитель: Sigma
- Каталожный номер:
G5635 - CAS номер : 9031-11-2
Packaging
1000, 3000, 5000, 15000 units in serum bottle
Unit Definition
One unit will hydrolyze 1.0 μmole of o-nitrophenyl β-
Physical form
Contains Tris buffer salts and magnesium chloride
Application
β-Galactosidase is conjugated to an antibody which specifically recognizes a target molecule (enzyme immunoassay or EIA).1 β-Galactosidase is also used as a reporter enzyme to monitor the level of gene expression of a promoter.2 It may be used as a positive control protein with anti-β-galactosidase antibodies.
Biochem/physiol Actions
β-galactosidase cleaves lactose into its monosaccharide components, glucose and galactose. It also catalyses the transglycosylation of glucose into allolactose, the inducer of β-galactosidase, in a feedback loop.3
General description
β-Galactosidase is a tetramer consisting of four equal subunits of 135,000 each. It is a sulfhydryl containing enzyme, with 19 cysteine residues per subunit.4
Physical properties
Tetramer molecular weight 465 kDa (subunits 116.3 kDa each)
Характеристики реактива | |
storage temp. | −20°C |