Recombinant snake venom prothrombin activators

Abstract

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.

Prokaryotic expression, evaluation, and prediction of the structure and function of the ecarin metalloproteinase domain

“…I-TASSER, Iterative Threading ASSEmbly Refinement toxins, ecarin has the ability to activate prothrombin and convert it into active thrombin without the need for additional cofactors, without making any biological difference between carboxylated and noncarboxylated prothrombin. 23 In 2016, Macalin et al transformed the expression vector pPR033 containing ecarin into BL21 cells. These scientists proposed the use of the disulfide bond C system to solve the problem of disulfide bonding of proteins produced in bacterial cells.…”

Snake Venoms in Drug Discovery: Valuable Therapeutic Tools for Life Saving

“…Ecarin is a metalloprotease isolated from the venom of the saw-scaled viper ( Echis carinatus ) and used as prothrombin activator. Ecarin does not affect other clotting factors [211,212].…”

Snake Venom Components Affecting the Coagulation System

“…Despite this finding, specific FVII activators are not known. Oscutarin C was produced recently in its recombinant form (Lövgren 2013).…”

“…This protein is structurally similar to mammalian FX. Its complete amino acid sequence was described and the complete molecule produced in its recombinant form (Lövgren 2013).…”