| Texto completo | |
| Autor(es): |
Branco, Vania G.
;
Iqbal, Asif
;
Alvarez-Flores, Miryam P.
;
Sciani, Juliana M.
;
de Andrade, Sonia A.
;
Iwai, Leo K.
;
Serrano, Solange M. T.
;
Chudzinski-Tavassi, Ana M.
Número total de Autores: 8
|
| Tipo de documento: | Artigo Científico |
| Fonte: | BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS; v. 1864, n. 10, p. 1428-1435, OCT 2016. |
| Citações Web of Science: | 6 |
| Resumo | |
Background: Cancer has long been associated with thrombosis and many of the standard chemotherapeutics used to treat cancer are pro-thrombotic. Thus, the identification of novel selective anticancer drugs that also have antithrombotic properties is of enormous significance. Amblyomin-X is an anticancer protein derived from the salivary glands of the Amblyomma cajennense tick. Methods: In this work, we determined the inhibition profile of Amblyomin-X and its effect on activated partial thromboplastin time (aPTT) and prothrombin time (PT), using various approaches such as, kinetic analyses, amidolytic assays, SDS-PAGE, and mass spectrometry. Results: Amblyomin-X inhibited factor Xa, prothrombinase and tenase activities. It was hydrolyzed by trypsin and plasmin. MS/MS data of tryptic hydrolysate of Amblyomin-X suggested the presence of Cys(8)-Cys(59) and Cys(19)-Cys(42) but not Cys(34)-Cys(55) disulfide bond. Instead of Cys(34)-Cys(55), two noncanonical Cys(34)-Cys(74) and Cys(55)-Cys(74) disulfide bonds were identified. Furthermore, when Amblyomin-X (1 mg/kg) injected in rabbits, it prolonged aPTT and PT. Conclusion: Amblyomin-X is a noncompetitive inhibitor (K-i = 3.9 mu M) of factor Xa. It is a substrate for plasmin and trypsin, but not for factor Xa and thrombin. The disulfide Cys(34)-Cys(55) bond probably scrambles with inter chain seventh free cysteine residues (Cys(74)) of Amblyomin-X. The prolongation of PT and aPTT is reversible. General Significance. In term of anticoagulant property, this is structural and functional characterization of Amblyomin-X. All together, these results and previous findings suggest that Amblyomin-X has a potential to become an anticancer drug with antithrombotic property. (C) 2016 Elsevier B.V. All rights reserved. (AU) | |
| Processo FAPESP: | 13/07467-1 - CeTICS - Centro de Toxinas, Imuno-Resposta e Sinalização Celular |
| Beneficiário: | Hugo Aguirre Armelin |
| Modalidade de apoio: | Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs |
| Processo FAPESP: | 15/50040-4 - Rational approach for searching molecular targets involved in inflammatory events and cell survival |
| Beneficiário: | Ana Marisa Chudzinski-Tavassi |
| Modalidade de apoio: | Auxílio à Pesquisa - Programa Centros de Pesquisa em Engenharia |