title: Peptide hydrolases of Lactobacillus casei: isolation and general properties of various peptidase activities.
abstract: Discovery of an endopeptidase by gel chromatography and separation of 3 exopeptidases (a dipeptidase, an aminopeptidase and a specific carboxypeptidase) from Lactobacillus casei NCDO 151 by affinity chromatography is described. The 3 exopeptidases were strongly inhibited by the metal chelators EDTA and 1,10-phenanthroline but were reactivated with Co2+ and Mn2+. The pH optima for aminopeptidase, dipeptidase and carboxypeptidase activities were 6.5, 7.6 and 7.2, respectively. Maximum activity was obtained at 45 degrees C for the aminopeptidase, at 30 degrees C for the dipeptidase and at 40 degrees C for the carboxypeptidase. The substrate specificities of the 3 enzymes were also studied. The properties of these 3 enzymes are compared with those of other bacteria.
mesh_terms: D000626:Aminopeptidases / Q000378:metabolism; D002268:Carboxypeptidases / Q000378:metabolism; D004150:Dipeptidases / Q000378:metabolism; D004355:Drug Stability; D010450:Endopeptidases / Q000378:metabolism; D007700:Kinetics; D007780:Lacticaseibacillus casei / Q000201:enzymology*; D010447:Peptide Hydrolases / Q000302:isolation & purification / Q000378:metabolism*; D013379:Substrate Specificity
chemical_list: D002268:Carboxypeptidases; D010450:Endopeptidases; D010447:Peptide Hydrolases; D000626:Aminopeptidases; D004150:Dipeptidases