The Procoagulant Snake Venom Serine Protease Potentially Having a Dual, Blood Coagulation Factor V and X-Activating Activity

Abstract

A procoagulant snake venom serine protease was isolated from the venom of the nose-horned viper (Vipera ammodytes ammodytes). This 34 kDa glycoprotein, termed VaaSP-VX, possesses five kDa N-linked carbohydrates. Amino acid sequencing showed VaaSP-VX to be a chymotrypsin-like serine protease. Structurally, it is highly homologous to VaaSP-6 from the same venom and to nikobin from the venom of Vipera nikolskii, neither of which have known functions. VaaSP-VX does not affect platelets. The specific proteolysis of blood coagulation factors X and V by VaaSP-VX suggests that its blood-coagulation-inducing effect is due to its ability to activate these two blood coagulation factors, which following activation, combine to form the prothrombinase complex. VaaSP-VX may thus represent the first example of a serine protease with such a dual activity, which makes it a highly suitable candidate to replace diluted Russell’s viper venom in lupus anticoagulant testing, thus achieving greater reliability of the analysis. As a blood-coagulation-promoting substance that is resistant to serpin inhibition, VaaSP-VX is also interesting from the therapeutic point of view for treating patients suffering from hemophilia.

Venom-Induced Blood Disturbances by Palearctic Viperid Snakes, and Their Relative Neutralization by Antivenoms and Enzyme-Inhibitors

“…Great diversity may exist within each of these toxin classes. For example, a SVSP isolated from V. ammodytes venom (VaaSP-VX) has been shown to activate Factor X (FX) and Factor V (FV) simultaneously, a function congruent with the metalloproteases in this study (although this toxin is in much lower levels in the venom than the metalloprotease), while another V. ammodytes SVSP (VaF1 toxin) has α-fibrinogenolytic activity ( 70 , 71 ). Another V. ammodytes toxin, a myotoxic secreted PLA 2 analogue ammodytin L (AtnL) was reported to cause irreversible atrioventricular (AV) blockade ( 72 , 73 ).…”

Separation and Analytical Techniques Used in Snake Venomics: A Review Article

“…Similarly, a Mono S CEX column was used to further separate fractions generated by the SEC of Vipera ammodytes venom. The peak of interest was homogeneous, showing one band on SDS-PAGE and proving the high resolution of CEX as a second step of the purification process [14]. On the other hand, an SV metalloproteinase was isolated using CEX as a first step, which required a supplementary purification step to reach the pure protein [18].…”

“…Likewise, a snake venom serine proteinase was isolated from Vipera ammodytes ammodyets venom using Sephacryl S-200 SEC as a first chromatographic step. Further fractionation of the peak of interest yielded 11 fractions, demonstrating the low resolution of SEC [14]. Consequently, SEC is valuable for the partition of snake venom proteins by size groups; however, it must be followed by other separation techniques, since it has an inherently low resolution and is incapable alone of isolating a single molecule from the mixture.…”

“…In fact, SVs are separated by SDS-PAGE followed by in-gel protein digestion and mass spectrometry for protein identification [44]. A chromatography step might also be added before gel separation to improve resolution and enhance protein coverage [14]. For example, HPLC fractions of Crotalus durissus crude venom were separated using SDS-PAGE under reducing conditions; bands were excised, digested, and subjected to mass spectrometry for protein identification [45].…”

A Review on Anti-Thrombotic Agents Derived from Snake Venom Protein

“…Thrombosis is the formation of clots in the blood vessels and leads to partial or complete obstruction, and a decrease in the amount of blood flowing in the blood vessels, because of changes in persistent blood components [4,16]. This picture displays the paths of coagulation and the mechanism of several components of anticoagulant snake venoms [30]. Enzymatic Anticoagulant Proteins Phospholipase A2 (PLA2): Phospholipase A2 is a superfamily it is a toxic enzyme in snake venom [30].…”