Analysis Note

amidase and esterase activities may be present

Application

Carboxypeptidase Y has a broad specificity and is stable in urea. Hence, this enzyme is not like other carboxypeptidases and can be used for sequence analysis. Due to its amidase action, this enzyme might be applied to the sequence analysis of peptides having amidated COOH-terminal groups such as oxytocin and vasopressin.

Biochem/physiol Actions

The glycoprotein has a molecular weight of about 61,000, has a nitrogen content of 12.74%. It is a single polypeptide chain of 442 residues with 16 residues of glucosamine in the carbohydrate moiety. Lysine is at the NH2 terminus and -Asp-Ser-Thr-Leu is the COOH-terminal sequence. The principal action of the enzyme is to remove COOH-terminal residues from polypeptide chains. It is used as a vacuolar marker enzyme for studies on protein transport and localization.

Packaging

Package size based on protein content

1, 5 mg in glass bottle

Physical form

Lyophilized powder containing citric acid.

Unit Definition

One unit will hydrolyze 1.0 µmole of N-CBZ-Phe-Ala to N-CBZ-L-phenylalanine and L-alanine per min at pH 6.75 at 25°C, based on EM/230 = 191.5.