tailieunhanh - Báo cáo khoa học: Temperature and salts effects on the peptidase activities of the recombinant metallooligopeptidases neurolysin and thimet oligopeptidase

We report the recombinant neurolysin and thimet oligo-peptidase (TOP) hydrolytic activities towards internally quenched fluorescent peptides derived from the peptide Abz-GGFLRRXQ-EDDnp (Abz,ortho-aminobenzoicacid; EDDnp,N-(2,4-dinitrophenyl) ethylenediamine), in which X was substituted by 11 different natural amino acids. Neurolysin hydrolyzed these peptides at R–R or at R–X bonds, and TOP hydrolyzed at R–R or L–R bonds, showing a preference to cleave at three or four amino acids from the C-terminal end. . | Eur. J. Biochem. 269 4326-4334 2002 FEBS 2002 doi Temperature and salts effects on the peptidase activities of the recombinant metallooligopeptidases neurolysin and thimet oligopeptidase Vitor Oliveira1 Revnaldo Gatti2. Vanessa Rioli3. Emer S. Ferro3. Alberto Snisni2 4 Antonio C M. Camarao5 B B B Maria Ab Juliano1 and Luiz Juliano1 1Department of Biophysics Escola Paulista de Medicina Sao Paulo Brazil 2Centro de Biologia Molecular Estrutural National Laboratory of Synchrotron Light CBME-LNLS Campinas Brazil 3Department of Histology Institute of Biomedical Sciences Universidade de Sao Paulo Brazil 4Department of Experimental Medicine University of Parma Parma 43100 Italy 5 Laboratory of Biochemistry and Biophysics Instituto Butantan Sao Paulo Brazil We report the recombinant neurolysin and thimet oligopeptidase TOP hydrolytic activities towards internally quenched fluorescent peptides derived from the peptide Abz-GGFLRRXQ-EDDnp Abz ortho-aminobenzoicacid EDDnp N- 2 4-dinitrophenyl ethylenediamine in which X was substituted by 11 different natural amino acids. Neurolysin hydrolyzed these peptides at R-R or at R-X bonds and TOP hydrolyzed at R-R or L-R bonds showing a preference to cleave at three or four amino acids from the C-terminal end. The kinetic parameters of hydrolysis and the variations of the cleavage sites were evaluated under different conditions of temperature and salt concentration. The relative amount of cleavage varied with the nature of the substitution at the X position as well as with temperature and NaCl concentration. TOP was activated by all assayed salts in the range M for NaCl KCl NH4Cl and Nal and M for Na2SO4. Concentration higher than N NH4Cl and Nal reduced TOP activity while N or higher concentration of NaCl KCl and Na2SO4 increased TOP activity. Neu-rolysin was strongly activated by NaCl KCl and Na2SO4 while NH4Cl and Nal have very modest effect. High positive values of enthalpy