Characterization of the pcpgene encoding the pyrrolidone carboxyl peptidase of Bacillus subtilis

Pyrrolidone carboxyl peptidase (EC 3.4.11.8) (Pcp) is an enzyme that catalyzes the removal of the N-terminal pyroglutamyl group from some poptides or proteins. Its value in protein chemistry and bacterial diagnosis makes this enzyme an interesting subject of study. The present paper reports for the first time the cloning and characterization of a pyrrolidone carboxyl peptidase gene ( pcp). This gene is present in a single copy in the genome of Bacillus subtilisas indicated by Southern blot hybridization analysis. The pcptranscripts were analyzed in Escherichia coliby Northern blot hybridization and S1 nuclease mapping. The deduced amino acid sequence predicts a protein of 215 amino acids with a calculated molecular weight of 23,777 Da. The pcpgene has been over-expressed in E. coli, allowing the identification and partial characterization of Pcp protein.