Sigma-Aldrich Carboxypeptidase A. Cleaves C-terminal amino acids, suitable for Mass Spectrometry, from bovine pancreas. 500 units

Carboxypeptidase A (CPA) is a secreted protease is liberated after the activation of mast cells to facilitate acute anaphylaxis. Carboxypeptidase A has a long half-life in vivo, when compared to other secreted proteases.[1]

Carboxypeptidase A from bovine pancreas has been used in in vitro simulated digestion.[2]

Carboxypeptidase A from bovine pancreas has been used in a study to investigate the expression of a soluble and activatable form of bovine procarboxypeptidase A in Escherichia coli. Carboxypeptidase A from bovine pancreas has also been used in a study to investigate the isolation and partial characterization of precursor forms of ostrich carboxypeptidase.

Carboxypeptidase as isolated from bovine pancreas glands is a metalloenzyme that contains 1 g atom of zinc per mole of protein.[3] It catalyzes the hydrolysis of the carboxyl-terminal peptide bond in peptides and proteins. It is primarily specific to aromatic and hydrophobic side chains such as phenylalanine, tryptophan or leucine. The enzyme also exhibits esterase activity. It is inhibited by β-phenylpropionate and indole acetate.†

Treated with phenylmethylsulfonyl fluoride to eliminate trypsin and chymotrypsin activity. Dialyzed and recrystallized: aqueous suspension with toluene added.

Protein determined by E1%/278

One unit will hydrolyze 1.0 μmole of hippuryl-L-phenylalanine per min at pH 7.5 at 25 °C.