Carboxypeptidase B - Assay

Source:
Porcine Pancreas
CAS:
9025-24-5
EC:
3.4.17.2

Carboxypeptidase B Assay

Method
Activity is measured by the spectrophotometric method of Folk et al. (1960) where the reaction velocity is determined by an increase in absorbance at 254 nm resulting from the hydrolysis of hippuryl-L-arginine. One unit causes the hydrolysis of one micromole of hippuryl-L-arginine per minute at 25°C and pH 7.65 under the specified conditions.
Reagents
  • 0.025 M Tris⋅HCl buffer, pH 7.65 containing 0.1 M sodium chloride
  • 0.001 M Hippuryl-L-arginine in 0.025 M Tris⋅HCl pH 7.65 containing 0.1 M sodium chloride
Enzyme

Dilute stock solution with reagent grade water to a concentration of 1-5 units/ml.

equation

Procedure

Set spectrophotometer at 254 nm and 25°C.

Pipette 2.9 ml of substrate into cuvette and incubate in spectrophotometer at 25°C for 3-4 minutes to reach temperature equilibration and establish blank rate, if any. Add 0.1 ml of diluted enzyme and record increase in A254 for 3-4 minutes. Determine ΔA254/minute from the initial linear portion of the curve.

Calculation

where 0.349 is the extinction coefficient of hippuric acid formed during the reaction

Carboxypeptidase B Products

Description
Activity
Code
Cat. #
Size
Price
Description
Carboxypeptidase B
Source:
Porcine Pancreas
Chromatographically purified. A solution in 100mM sodium chloride. Chymotrypsin and trypsin 0.02%.
Store at -20°C.
Ice Pack required
Activity
≥170 units per mg protein
Code
COBC
LS005305
5 mg
$96.00
LS005301
10 mg
$167.00
LS005304
50 mg
$710.00
LS005302
Bulk
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The minimum amount for bulk packaging/pricing for this product is 1000 x 1 mg. Please contact custservice@worthington-biochem.com to request a quote for smaller amounts.