β-Galactosidase, Recombinant, 1000 U

Prepare a 1 mg/mL stock solution in 0.10M sodium/potassium phosphate buffer pH 7.0. Immediately prior to use, dilute further to 0.02-0.04% in enzyme diluent. The protein concentration of the chromatographically purified enzyme may be determined as follows: mg Protein/ml = A280 x 0.478

Note: This enzyme is not stable when diluted. All dilutions should be made as quickly as possible and used immediately.

Specific Activity: ≥ 300 units per mg protein

Unit Definition: 1 unit hydrolyzes 1umole o-nitrophenyl-beta-D-galactopyranoside (ONPG) per min. at 25°C, pH 7.5 (Craven et al., 1965).