Kininogenase activity by the major cysteinyl proteinase (Cruzipain) from Trypanosoma cruzi

• Autor(a) principal: Del Nery, Elaine [UNIFESP]
• Data de Publicação: 1997
• Outros Autores: Juliano, Maria Aparecida [UNIFESP], Lima, Ana Paula CA, Scharfstein, Julio, Juliano, Luiz [UNIFESP]
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNIFESP
• Texto Completo: http://dx.doi.org/10.1074/jbc.272.41.25713; http://repositorio.unifesp.br/handle/11600/25797

The major isoform of Trypanosona cruzi cysteinyl proteinase (cruzipain) has generated Lys-bradykinin (Lys-BK or kallidin), a proinflammatory peptide, by proteolysis of kininogen. the releasing of this peptide was demonstrated by mass spectrometry, radioimmunoassay, and ileum contractile responses, the kinin-releasing activity was immunoabsorbed selectively by monoclonal antibodies to the characteristic COOH-terminal domain of cruzipain. To determine the hydrolysis steps that account for the kininogenase activity of cruzipain, we synthesized a fluorogenic peptide (o-aminobenzoyl-Leu-Gly-Met-Ile-Ser-Leu-Met-Lys-Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg(389)-Ser(390)-Ser-Arg-Ile-NH2) based on the sequence Leu(373) to Ile(393) of the human high molecular weight kininogen, the hydrolysis products from this peptide were isolated by high performance liquid chromatography, and Lys-BK was characterized as the major released kinin by mass spectrometry. Intramolecularly quenched fluorogenic peptides spanning the Met(379)-Lys(380) and Arg(389)-Ser(390) bradykinin-flanking sequences were then used to assess the substrate specificity re requirements of the parasite-derived protease compared with two COOH-terminal truncated recombinant isoforms (cruzain and cruzipain 2). in contrast to the high catalytic efficiency of parasite-derived cruzipain, the recombinant proteinases cleaved the bradykinin-flanking sites at markedly different rates. in addition, we also demonstrated that cruzipain activates plasmatic prekallikrein, which would be a second and indirect way of the parasite protease to release bradykinin.