Radiochemical determination of a unique sequence around the reactive serine residue of a di-isopropyl phosphorofluoridate-sensitive plant carboxypeptidase and a yeast peptidase.
Phaseolain, a carboxypeptidase from French-bean leaves, and a partially purified peptidase from baker's yeast are inhibited by reaction with di-isopropyl phosphorofluoridate. Radioactive di-isopropyl [(32)P]phosphorofluoridate was used to show that the site of reaction is a unique serine residue and that the sequence of amino acids adjacent to the reactive serine is Glu-Ser-Tyr. This sequence is different from those of other ;serine' enzymes previously reported and, for phaseolain, represents an unequivocal example of a ;serine' carboxypeptidase.
D000595:Amino Acid Sequence; D002268:Carboxypeptidases; D002848:Chromatography, DEAE-Cellulose; D002850:Chromatography, Gel; D004586:Electrophoresis; D005461:Fluorine; D006868:Hydrolysis; D007531:Isoflurophate; D010447:Peptide Hydrolases; D010759:Phosphorus Isotopes; D010944:Plants / Q000201:enzymology; D012441:Saccharomyces cerevisiae / Q000201:enzymology; D012694:Serine
D010759:Phosphorus Isotopes; D007531:Isoflurophate; D005461:Fluorine; D012694:Serine; D002268:Carboxypeptidases; D010447:Peptide Hydrolases