cDNA cloning and complete primary structure of the small, active subunit of human carboxypeptidase N (kininase 1).
The human plasma metallo-protease carboxypeptidase N of Mr 280,000 consists of two small, enzymatically active subunits of Mr 50,000 and two large subunits. Only the large subunits are glycosylated. They may have a function in stabilizing the complex in plasma. The N-terminal sequence of the small subunit was determined from the isolated protein and used to specify a unique 59-mer oligonucleotide probe. A cDNA clone of 1.7 kbp containing the entire coding sequence of the small subunit of carboxypeptidase N was isolated from a human-liver cDNA library. The cDNA clone encodes a signal sequence of 20 amino acids and the 438 amino acids of the mature subunit. There is a remarkable primary structure similarity of 49% to bovine carboxypeptidase E (enkephalin convertase). A more distant relationship to the bovine pancreatic, digestive carboxypeptidases A and B or even to the metallo-endopeptidases is based mainly on the occurrence of conserved, mechanistically important residues.
Gebhard
W
W
Abteilung für Klinische Chemie, Universität München, Federal Republic of Germany.
Schube
M
M
Eulitz
M
M
D000595:Amino Acid Sequence; D001483:Base Sequence; D002268:Carboxypeptidases / Q000235:genetics*; D003001:Cloning, Molecular; D004247:DNA / Q000097:blood / Q000235:genetics*; D005796:Genes; D006801:Humans; D001121:Lysine Carboxypeptidase / Q000097:blood / Q000235:genetics*; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D011487:Protein Conformation; D012689:Sequence Homology, Nucleic Acid
D046911:Macromolecular Substances; D004247:DNA; D002268:Carboxypeptidases; D001121:Lysine Carboxypeptidase