C5233

Carboxypeptidase B from human pancreas

50-55 units/mg protein carboxypeptidase B

• Synonym(s): Peptidyl-L-Lysine[L-arginine] hydrolase
• CAS Number: 9025-24-5
• Enzyme Commission number: 3.4.17.2 (BRENDA, IUBMB)
• MDL number: MFCD00081476
• UNSPSC Code: 12352204
• PubChem Substance ID: 24892769
• NACRES: NA.54

Properties

• biological source: human pancreas
• Quality Level: 200
• form: solution
• specific activity: 50-55 units/mg protein carboxypeptidase B
• impurities: ≤0.2% chymotrypsin; ≤0.2% trypsin; ≤1 unit/mg protein carboxypeptidase A
• UniProt accession no.: P15086
• shipped in: dry ice
• storage temp.: −20°C
• SMILES string: S(Cc3ccccc3)C(=O)C(NC(=O)C2N(CCC2)C(=O)C(NC(=O)C(NC(=O)CCC(=O)O)C)C)Cc1ccccc1
• InChI: 1S/C31H38N4O7S/c1-20(32-26(36)15-16-27(37)38)28(39)33-21(2)30(41)35-17-9-14-25(35)29(40)34-24(18-22-10-5-3-6-11-22)31(42)43-19-23-12-7-4-8-13-23/h3-8,10-13,20-21,24-25H,9,14-19H2,1-2H3,(H,32,36)(H,33,39)(H,34,40)(H,37,38)
• InChI key: TWURVFFNODFJBJ-UHFFFAOYSA-N
• Gene Information: human ... CPB1(1360)

Description

General description

Carboxypeptidase B is mapped to human chromosome 3q24.[1] Carboxypeptidase B belongs to A/B subfamily of carboxypeptidases.[2]

Application

Carboxypeptidase B from Sigma has been used as a reference for assaying carboxypeptidase activity in lysed pituitary granules derived from the anterior and intermediate lobes of rat.[3] The enzyme has also been used to digest plasma samples by removing C-terminal basic amino acids, to get a distinct band for each allotype during C4 electrophoresis.[4]

Biochem/physiol Actions

Carboxypeptidase B (or peptidyl-L-lysine (-L-arginine) hydrolase) catalyzes the hydrolysis of the basic amino acids, lysine, arginine, and ornithine from the C-terminal position of polypeptides. It has been shown to be a single polypeptide of 34,000 Da. Trypsin is capable of converting native enzyme to the active enzyme, carboxypeptidase B II in vitro.[5] The optimum pH is found to be 9.0. The enzyme may be used for sequence analysis by successive cleavage of C-terminal basic amino acids. It can also be used as a serum marker for the diagnosis of acute pancreatitis.

Mutations in the carboxypeptidase B (CPB1) gene is implicated with increased susceptibility to pancreatic cancer development and progression.[6] Elevated levels of CPB1 is associated with low grade breast tumors and lymph node positive grade 1 tumors.[7]

Unit Definition

One unit will hydrolyze 1 μmole of hippuryl-L-arginine per minute at pH 7.7 at 25 °C

Physical form

Solution in 0.05 M NaOAc pH 5.0 + 1.0 M NaCl + 0.01% NaN₃

Safety Information

• Storage Class Code: 12 - Non Combustible Liquids
• WGK: WGK 1
• Flash Point(F): Not applicable
• Flash Point(C): Not applicable