CLONING, SEQUENCING AND EXPRESSION OF THE GENE ENCODING A MAJOR ALLOTYPIC PREPROCARBOXYPEPTIDASE-A FROM BOVINE PANCREAS

A cDNA encoding one of two major allotypic forms of bovine pancreatic preprocarboxypeptidase A (preproCPA) has been cloned, and its entire n ucleotide (nt) sequence determined. The cloned cDNA contains a 26-nt T -noncoding region, a 1260-nt open reading frame and a 51-nt 3'-noncodi ng region. The amino acid (aa) sequence deduced from the gene sequence contains Ile(179), Ala(228) and Val(305) at allotypic aa residues. Th e procarboxypeptidase A (proCPA) was produced in yeast and secreted in to the medium. Upon treatment with trypsin, proCPA generated an active enzyme with the same size as the mature carboxypeptidase A (CPA), as analyzed by use of anti-CPA polyclonal antibody.