Amblyomin-X having a Kunitz-type homologous domain, is a noncompetitive inhibitor of FXa and induces anticoagulation in vitro and in vivo
Biochim. Biophys. Acta, Proteins Proteomics
; 1824(10): p. 1428-1435, 2016.
Artigo
| Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP
| ID: but-ib14259
Biblioteca responsável:
BR78.1
Localização: BR78.1
ABSTRACT
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.
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Coleções:
Bases de dados nacionais
/
Brasil
Base de dados:
Sec. Est. Saúde SP
/
SESSP-IBPROD
Assunto principal:
Farmacologia
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Bioquímica
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Oncologia
Revista:
Biochim. Biophys. Acta, Proteins Proteomics
Ano de publicação:
2016
Tipo de documento:
Artigo