title: Structural requirements of bioactive peptides for interaction with endopeptidase 22.19.
abstract: A series of biologically active peptides and related compounds (opioid peptides, neurotensin, and bradykinin) were used as substrates or competitive inhibitors to study the structural requirements for peptide interaction with endopeptidase 22.19. The kinetics of hydrolysis of these peptides indicated that, in contrast to other proteases, the substrate specificity of endopeptidase 22.19 is not determined by the amino acids flanking the sensitive bonds of the substrates. The competition between bioactive peptide analogues and the quenched fluorescence substrate of endopeptidase 22.19 indicated that their length and their flexibility may be the dominant factors to explain their binding specificities. These peculiar features of endopeptidase 22.19 may be of importance to understand the physiological processes of conversion and inactivation of biologically active peptides.
authors.affiliation: Department of Pharmacology, Faculty of Pharmacy, University of São Paulo, Brazil.
authors.forename: A C
authors.initials: AC
authors.lastname: Camargo
authors.forename: M D
authors.initials: MD
authors.lastname: Gomes
authors.forename: O
authors.initials: O
authors.lastname: Toffoletto
authors.forename: M J
authors.initials: MJ
authors.lastname: Ribeiro
authors.forename: E S
authors.initials: ES
authors.lastname: Ferro
authors.forename: B L
authors.initials: BL
authors.lastname: Fernandes
authors.forename: K
authors.initials: K
authors.lastname: Suzuki
authors.forename: Y
authors.initials: Y
authors.lastname: Sasaki
authors.forename: L
authors.initials: L
authors.lastname: Juliano
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001920:Bradykinin / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism; D001921:Brain / Q000201:enzymology; D004399:Dynorphins / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism; D008666:Metalloendopeptidases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D008969:Molecular Sequence Data; D009479:Neuropeptides / Q000737:chemistry* / Q000378:metabolism* / Q000494:pharmacology; D009842:Oligopeptides / Q000737:chemistry / Q000378:metabolism; D011817:Rabbits; D013329:Structure-Activity Relationship; D013379:Substrate Specificity; D008083:beta-Lipotropin / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism
chemical_list: D009479:Neuropeptides; D009842:Oligopeptides; C060209:deltorphin II, Ala(2)-; D004399:Dynorphins; D008083:beta-Lipotropin; D008666:Metalloendopeptidases; C022510:thimet oligopeptidase; D001920:Bradykinin