Blanco_1998_Eur.J.Biochem_256_369

Reference

Title : Dipeptidyl-peptidase IV-beta--further characterization and comparison to dipeptidyl-peptidase IV activity of CD26 - Blanco_1998_Eur.J.Biochem_256_369
Author(s) : Blanco J , Nguyen C , Callebaut C , Jacotot E , Krust B , Mazaleyrat JP , Wakselman M , Hovanessian AG
Ref : European Journal of Biochemistry , 256 :369 , 1998
Abstract : Dipeptidyl peptidase IV-beta (DPP IV-beta) is a novel protein which shows a peptidase activity similar to the T-cell-activation antigen CD26. To further characterize this DPP IV-beta and confirm its cell surface expression, we have developed a purification strategy using the CD26- cell line C8166. The purification process includes biotinylation of cell surface proteins before preparation of cell extracts and processing by gel-filtration, ion-exchange and lectin chromatographies. Consistent with the molecular mass of DPP IV-beta estimated by gel-filtration chromatography, the final purified fraction, manifesting a typical DPP IV activity, showed a major biotinylated 75-80-kDa band in SDS/PAGE, thus suggesting the monomeric nature of this enzyme. Kinetic parameters of DPP IV-beta and the sensitivity to a new family of irreversible DPP IV inhibitors, were studied in comparison to CD26. Both enzymes followed a Michaelis kinetics with different Km values for Gly-Pro-NH-Np (NH-Np, para-nitroanilide) hydrolysis (0.28+/-0.05 mM and 0.12+/-0.02 mM). More significant differences were observed in the sensitivity to inhibitors, which exerted a much higher activity on CD26 than on DPP IV-beta. These differences permitted us to study DPP IV-beta expression in CD26-expressing cells, showing the expression of this new enzyme in all lymphoid cells tested, and a rapid enhancement in phytohemagglutinin-stimulated or protein-A-stimulated peripheral blood mononuclear cells. Our results indicate that, although DPP IV-beta and CD26 are coexpressed and manifest a typical DPP IV activity, there are distinct features in their catalytic activities that may confer to each enzyme a complementary role in peptide processing.
ESTHER : Blanco_1998_Eur.J.Biochem_256_369
PubMedSearch : Blanco_1998_Eur.J.Biochem_256_369
PubMedID: 9760177

Related information

Citations formats

Blanco J, Nguyen C, Callebaut C, Jacotot E, Krust B, Mazaleyrat JP, Wakselman M, Hovanessian AG (1998)
Dipeptidyl-peptidase IV-beta--further characterization and comparison to dipeptidyl-peptidase IV activity of CD26
European Journal of Biochemistry 256 :369

Blanco J, Nguyen C, Callebaut C, Jacotot E, Krust B, Mazaleyrat JP, Wakselman M, Hovanessian AG (1998)
European Journal of Biochemistry 256 :369