| Texto completo | |
| Autor(es): |
Rioli, Vanessa
;
Gozzo, Fabio C.
;
Heimann, Andrea S.
;
Linardi, Alessandra
;
Krieger, José E.
;
Shida, Cláudio S.
;
Almeida, Paulo C.
;
Hyslop, Stephen
;
Eberlin, Marcos N.
;
Ferro, Emer S.
[10]
Número total de Autores: 10
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Journal of Biological Chemistry; v. 278, n. 10, p. 8547-8555, Mar. 2003. |
| Área do conhecimento: | Ciências Biológicas - Morfologia |
| Assunto(s): | Complexo principal de histocompatibilidade Peptidil dipeptidase A Peptídeo hidrolases Ácidos aminoisobutíricos Óxido nítrico |
| Resumo | |
Endopeptidase 24.15 (EC 3.4.24.15; ep24.15), neurolysin (EC 3.4.24.16; ep24.16), and angiotensin-converting enzyme (EC 3.4.15.1; ACE) are metallopeptidases involved in neuropeptide metabolism in vertebrates. Using catalytically inactive forms of ep24.15 and ep24.16, we have identified new peptide substrates for these enzymes. The enzymatic activity of ep24.15 and ep24.16 was inactivated by site-directed mutagenesis of amino acid residues within their conserved HEXXH motifs, without disturbing their secondary structure or peptide binding ability, as shown by circular dichroism and binding assays. Fifteen of the peptides isolated were sequenced by electrospray ionization tandem mass spectrometry and shared homology with fragments of intracellular proteins such as hemoglobin. Three of these peptides (PVNFKFLSH, VVYPWTQRY, and LVVYPWTQRY) were synthesized and shown to interact with ep24.15, ep24.16, and ACE, with Ki values ranging from 1.86 to 27.76 µM. The hemoglobin -chain fragment PVNFKFLSH, which we have named hemopressin, produced dose-dependent hypotension in anesthetized rats, starting at 0.001 µg/kg. The hypotensive effect of the peptide was potentiated by enalapril only at the lowest peptide dose. These results suggest a role for hemopressin as a vasoactive substance in vivo. The identification of these putative intracellular substrates for ep24.15 and ep24.16 is an important step toward the elucidation of the role of these enzymes within cells. (AU) | |
| Processo FAPESP: | 01/07544-9 - Projeto genoma estrutural. |
| Beneficiário: | Emer Suavinho Ferro |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |
| Processo FAPESP: | 96/01451-9 - Anestésicos locais: síntese, propriedades estruturais e físico-químicas e interação com membranas modelo e biológicas |
| Beneficiário: | Shirley Schreier |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |
| Processo FAPESP: | 99/01983-9 - Bases moleculares e celulares da biologia da peptidases: projeto ii do laboratorio de comunicacao celular. |
| Beneficiário: | Emer Suavinho Ferro |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |
| Processo FAPESP: | 00/04297-8 - Modernização do setor multiusuários de Bioquímica e Biologia Molecular do Departamento de Histologia e Embriologia |
| Beneficiário: | Emer Suavinho Ferro |
| Modalidade de apoio: | Auxílio à Pesquisa - Programa Equipamentos Multiusuários |
| Processo FAPESP: | 00/11176-2 - Técnicas modernas em espectrometria de massas e suas aplicações em química e bioquímica |
| Beneficiário: | Marcos Nogueira Eberlin |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |