Purification and characterization of a proline iminopeptidase from Propionibacterium shermanii 13673

A proline lminopepndase activity was round in P shermanii 13673. The enzyme activity was present in the intracellular fraction. The peptidase was purifisd approximately 80 times by ionexchange chromatography on Fractogel T8K DEAE 650 and gel filtration on 8ephacryl 8-100 HR. The purified enzyme appeared as a single band after sodium dodecyl sulfate-polyacrylamide gel electrophoresis. It had a molecular weight of 61 000. Optima for activity of the.purified enzyme were 40 oC and pH 8.0. The enzymatic activity was inhibited by phenylmethylsulfonylfluoride (1 mM). Divalent ions Zn, Co, Cu and Fe alsohad an inhibitor}t effect. The peptidase hydrolyzed specifically Pro p-NA amino acid, dipeptides Pro-Met, Pro-Phe, Pro-Le, Pro-lieu, Pro-G1yand 13-casomorphin des-Tyr fragment 7. Propionibacterium shermanii 1 enzyme 1 peptidase 1 proline 1 purification Rsum -Purification et caractrisation d'une praline iminopeptidase partir de la souche Propionibacterium shermanii 13673. Une activit de proline iminopeptidase a t mise en vidence dans la souche P shermanii 13673. L'activit enzymatique est prsente dans la fraction intracellulaire. L'enzyme a t purifie environ 80 fois par chromatographie d'change d'ions sur fractogel TSK DEAE 650 et gel filtration sur Sephacryl S-100 HR. L'enzyme purifie prsente une seule bande aprs lectrophorse en gel de polyacrylamide et en prsence de SDS. 'Elle a un poids molculaire de 61 000. La temprature est de 40C et le pH optimal de 8,0. L'activit enzymatique est inhibe par le phnylmthylfulfonyl f1uoride (1 mM). Les ions divalents Zn, Co, Cu et Fe ont aussi un effet inhibiteur. La peptidase hydrolyse spcifiquement la Pro p-NA, les dipeptides Pro-Met, Pro-Phe, Pro-Leu, Pro-Ile, Pro-Gly et le fragment 7 des-Tyr de la {J-easomorphine. . Propionibacterium sherman li / enzyme / peptldase / proline / purification