Recombinant snake venom prothrombin activators
نویسنده
چکیده
Three prothrombin activators; ecarin, which was originally isolated from the venom of the saw-scaled viper Echis carinatus, trocarin from the rough-scaled snake Tropidechis carinatus, and oscutarin from the Taipan snake Oxyuranus scutellatus, were expressed in mammalian cells with the purpose to obtain recombinant prothrombin activators that could be used to convert prothrombin to thrombin. We have previously reported that recombinant ecarin can efficiently generate thrombin without the need for additional cofactors, but does not discriminate non-carboxylated prothrombin from biologically active γ-carboxylated prothrombin. Here we report that recombinant trocarin and oscutarin could not efficiently generate thrombin without additional protein co-factors. We confirm that both trocarin and oscutarin are similar to human coagulation Factor X (FX), explaining the need for additional cofactors. Sequencing of a genomic fragment containing 7 out of the 8 exons coding for oscutarin further confirmed the similarity to human FX.
منابع مشابه
Blood Coagulation Induced by Iranian Saw-Scaled Viper (Echis Carinatus) Venom: Identification, Purification and Characterization of a Prothrombin Activator
Objective(s): Echis carinatus is one of the venomous snakes in Iran. The venom of Iranian Echis carinatus is a rich source of protein with various factors affecting the plasma protein and blood coagulation factor. Some of these proteins exhibit types of enzymatic activities. However, other items are proteins with no enzymatic activity. Materials and Methods: In order to study the mechanism ...
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Several prothrombin activators from snake venoms have been isolated and characterized (For details, see 1). Initially, they were classified into three major groups based on their structural and functional properties (1, 2). They differ from each other in their cofactor requirements and the products formed. Group I activators are metalloproteinases. They convert prothrombin to meizothrombin and ...
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