| Autor: |
Bersanetti PA; Health Informatics Department, Universidade Federal de S ã o Paulo, Rua Botucatu 862, São Paulo, 04023-062, SP, Brazil., Sabatini RA, Matos BS, Douglas RG, Nchinda A, Juliano MA, Pesquero JB, Sturrock ED, Carmona AK |
| Jazyk: |
angličtina |
| Zdroj: |
Biological chemistry [Biol Chem] 2012 Dec; Vol. 393 (12), pp. 1547-54. |
| DOI: |
10.1515/hsz-2012-0170 |
| Abstrakt: |
Somatic angiotensin I-converting enzyme (ACE)has two homologous active sites (N and C domains) that show differences in various biochemical properties.In a previous study, we described the use of positionals canning synthetic combinatorial (PS-SC) libraries of fluorescence resonance energy transfer (FRET) peptides to define the ACE C-domain versus N-domain substrate specificity and developed selective substrates for the C-domain(Bersanetti et al., 2004). In the present work, we used the results from the PS-SC libraries to define the N-domain preferences and designed selective substrates for this domain. The peptide Abz-GDDVAK(Dnp)-OH presented the most favorable residues for N-domain selectivity in the P 3 to P 1 ′ positions. The fluorogenic analog Abz-DVAK(Dnp)-OH (Abz = ortho -aminobenzoic acid; Dnp = 2,4-dinitrophenyl)showed the highest selectivity for ACE N-domain( k cat /K m = 1.76 μ m -1 · s -1) . Systematic reduction of the peptide length resulted in a tripeptide that was preferentially hydrolyzed by the C-domain. The binding of Abz-DVAK(Dnp)-OH to the active site of ACE N-domain was examined using a combination of conformational analysis and molecular docking. Our results indicated that the binding energies for the N-domain-substrate complexes were lower than those for the C-domain-substrate, suggesting that the former complexes are more stable. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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