title: Degradation of neurotensin by rabbit brain endo-oligopeptidase A and endo-oligopeptidase B (proline-endopeptidase).
abstract: The degradation of neurotensin and D-Tyr11 neurotensin by apparently homogeneous preparations of rabbit brain endo-oligopeptidase A and endo-oligopeptidase B (Proline-endopeptidase) was studied. Peptide fragments were isolated by high performance liquid chromatography and identified by amino acid analysis. Endo-oligopeptidase A cleaved neurotensin at the Arg8-Arg9 bond whereas D-Tyr11 neurotensin was not significantly hydrolysed. Endo-oligopeptidase B cleaved at the carboxyl side of Pro7, Pro10 in neurotensin and at Pro7 in D-Tyr11 neurotensin. The concentration dependent inhibition of neurotensin degradation by bradykinin and vice-versa represents additional evidence that endo-oligopeptidase A cleaves both Phe5-Ser6 bond of bradykinin and the Arg8-Arg9 bond of neurotensin.
mesh_terms: D000818:Animals; D001921:Brain / Q000201:enzymology*; D002462:Cell Membrane / Q000201:enzymology; D002851:Chromatography, High Pressure Liquid; D003546:Cysteine Endopeptidases; D010450:Endopeptidases / Q000378:metabolism*; D007700:Kinetics; D009496:Neurotensin / Q000378:metabolism*; D010446:Peptide Fragments / Q000032:analysis; D007703:Peptidyl-Dipeptidase A / Q000378:metabolism*; D011817:Rabbits
chemical_list: D010446:Peptide Fragments; D009496:Neurotensin; D010450:Endopeptidases; D007703:Peptidyl-Dipeptidase A; D003546:Cysteine Endopeptidases; C028307:endopeptidase B