عربي
Skip Navigation Links
UniversityExpand University
CollegesExpand Colleges
CentersExpand Centers
Admin. UnitExpand Admin. Unit
StaffExpand Staff
StudentsExpand Students
 
Skip Navigation LinksHome Research Research Papers Paper Description    
 
Skip Navigation Links.
 
Paper Description


Lebecetin, a potent antiplatelet C-type lectin from Macrovipera lebetina venom


Authors: Sameh SARRAY, Najet Srairi, Mohamed Hatmi, José Luis, Hechmi Louzir, Imed Regaya, Hmida SLEMA, Jacques Marvaldi, et al
Abstract: A novel C-type lectin protein (CLP), lebecetin, was purified to homogeneity from the venom of Macrovipera lebetina by gel filtration on a Sephadex G75 column and ion exchange chromatography on Mono S column. Lebecetin is a basic protein with a pHi = 9.9 and migrates in SDS-PAGE as a single band or two distinct bands under nonreducing and reducing conditions, respectively. These results are further confirmed by MALDI-TOF mass spectrometry that indicates a molecular mass of 29779 Da for native lebecetin and molecular masses of 15015 and 16296 Da for a and h subunits, respectively. The N-terminal amino acid sequences of lebecetin subunits show a high degree of similarity with those of C-type lectin-like proteins. In addition, functional studies showed that lebecetin has a potent inhibitory effect on platelet aggregation induced by thrombin in a concentration-dependent manner. In contrast, no inhibitory effect is observed when platelets are exposed to thromboxane A2 (TxA2) mimetic (U46619) or arachidonic acid. Moreover, there was no effect either on blood coagulation or A, B and O washed human erythrocytes agglutination. Furthermore, flow cytometric analysis revealed that fluoro-isothiocyanate (FITC)-labelled lebecetin bound to human formalin fixed platelets in a saturable and concentration manner and this binding was specifically prevented by anti-glycoprotein Ib (GPIb) mAb. These observations suggest that lebecetin is a C-type lectin-like protein that selectively binds to platelet GPIb.
Published in: Biochimica et Biophysica Acta;1651():30-40
URL:
Copyright © 2010 Arabian Gulf University Contact: Tel:17239999, Fax:17272555 | Home | Location | site map| عربي |