The primary structure of carboxypeptidase S3 from Penicillium janthinellum IBT 3991

AbstractThe complete amino acid sequence of penicillopeptidase S3, a serine carboxypeptidase isolated from Penicillium janthinellum IBT 3991, has been determined. The enzyme consists of 481 amino acids arranged in a single polypeptide chain. Six glycosylation sites were established in positions 41, 218, 256, 326, 384 and 392. The molecule contains six cysteinyl residues among which disulfide bridges was established between Cys-71-Cys-333 and Cys-233-Cys-289. Carboxypeptidase S3 is homologous to carboxypeptidase PEPF (or carboxypeptidase I) from Aspergillus niger (67% identical positions). It is proposed that these enzymes form a separate sub-family among the serine carboxypeptidases