β-Galactosidase from Escherichia coli
SIGMA/G4155 - aqueous glycerol suspension, ≥500 units/mg protein (biuret)
Synonym: β-D-Galactoside galactohydrolase; Lactase
CAS Number: 9031-11-2
MDL Number: MFCD00155434
Product Type: Chemical
Stoichiometry: Lactose + H2O → D-Glucose + beta-D-Galactose
| form | aqueous glycerol suspension |
| mol wt | 465 kDa |
| Quality Level | 200  |
| specific activity | ≥500 units/mg protein (biuret) |
| storage temp. | −20°C |
| Application: | β-Galactosidase is used in the enzymatic assays in the synthesis of imidazolo-pyrrolidinoses. |
| 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. |
| General description: | Tetramer molecular weight 465 kDa (subunits 116.3 kDa each) |
| Other Notes: | Loss of enzymatic activity can occur if this enzyme is frozen. This enzyme is provided in a 50% glycerol solution and will not freeze if stored at -20° Celsius. It is not recommended that this enzyme preparation be stored in an ultracold freezer (-60 to -100° Celsius). |
| Other Notes: | One unit will hydrolyze 1.0 μmole of o-nitrophenyl β- |
| Packaging: | 5000, 15000 units in glass bottle |
| Physical form: | Suspension in 50% glycerol, 5 mM Tris buffer salts, 5 mM magnesium chloride, 0.5 mM DTT, 0.5 mM mercaptoethanol. pH 7.4 |
| RIDADR | NONH for all modes of transport |
| WGK Germany | WGK 2 |
| Flash Point(F) | Not applicable |
| Flash Point(C) | Not applicable |
| activity | specific activity: ≥500 units/mg protein (biuret) |
| Storage Temp. | −20°C |
| Enzyme Commission (EC) Number | 3.2.1.23 ( BRENDA  | IUBMB ) |
| UNSPSC | 12352204 |