title: Cloning and sequencing of chloroperoxidase cDNA.
abstract: An oligod-d(T) 12-18 primed cDNA library has been prepared from Caldariomyces fumago mRNA. A clone containing a full-length insert was sequenced on the supercoiled plasmid, pBR322. The complete primary sequence of chloroperoxidase has been derived. We have also determined about 73% of the peptide sequence by amino acid sequencing. The DNA sequence data matches all of the available known peptide sequences. The mature polypeptide contains 300 amino acids having a combined molecular weight of 32,974 daltons. A putative signal peptide of 21 amino acids is proposed from DNA sequence data. The chloroperoxidase gene encodes three potential glycosylation sites recognized as Asn-X-Thr/Ser sequences. Three cysteine residues are found in the protein sequence. A small region around Cys87 bears a minimal homology to the active site of cytochrome P450cam. No other heme protein homologues can be detected. We propose that Cys87 serves as a thiolate ligand to the iron of heme prosthetic group. A rare arginine codon, AGG, is used three times out of twelve in contrast to the very infrequent use of this codon in E. coli or yeast.
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002374:Catalase / Q000235:genetics; D002711:Chloride Peroxidase / Q000235:genetics*; D003001:Cloning, Molecular; D003062:Codon; D004247:DNA / Q000235:genetics; D004271:DNA, Fungal / Q000235:genetics; D005658:Fungi / Q000235:genetics*; D005800:Genes, Fungal; D010544:Peroxidases / Q000235:genetics*
chemical_list: D003062:Codon; D004271:DNA, Fungal; D004247:DNA; D010544:Peroxidases; D002711:Chloride Peroxidase; D002374:Catalase