@article {514,
	title = {Elucidation of procoagulant mechanism and pathophysiological significance of a new prothrombin activating metalloprotease purified from Daboia russelii russelii venom. (Mass Spectrometry)},
	journal = {Toxicon},
	volume = {100},
	year = {2015},
	month = {2015 Jun 15},
	pages = {1-12},
	abstract = {<p>The procoagulant proteases present in Russell{\textquoteright}s Viper venom (RVV) are responsible for promoting consumption coagulopathy in victims. In this study, a procoagulant metalloprotease (Rusviprotease) possessing prothrombin activating and α-fibrinogenase properties has been purified and characterized from RVV. Rusviprotease is a 26.8\&nbsp;kDa glycoprotein which also exists in other multimeric forms. The peptide mass fingerprinting and secondary structure analyses of Rusviprotease revealed its similarity with snake venom prothrombin activators and metalloproteases. Similar to group A prothrombin activators, Rusviprotease cleaved prothrombin independent of any co-factor requirement generating meizothrombin which is further cleaved to form thrombin. The Km and Vmax values of Rusviprotease towards prothrombin were determined to be 1.73\&nbsp;μM, and 153.5\&nbsp;nM thrombin generated/min/μmoles of Rusviprotease, respectively. The Km and Vmax values of Rusviprotease towards fibrinogen were calculated to be 3.14\&nbsp;μM and 78.7\&nbsp;nmol/min, respectively. Spectrofluorometric study provided the evidence of interaction between Rusviprotease and factor Xa with a Kd value of\&nbsp;6.64\&nbsp;nM. This interaction augmented the prothrombin activating property of the factor Xa-prothrombinase-Rusviprotease complex by 2.5 fold. Intravenous injection of Rusviprotease to BALB/c mice (0.1\&nbsp;mg/kg) resulted in in\&nbsp;vivo defibrinogenation rendering the blood incoagulable. In conclusion, Rusviprotease is the first example of a prothrombin activator with fibrinogenolytic property purified from Daboia russelii russelii venom.</p>
},
	keywords = {Animals, Blood Coagulation, Blood Platelets, Chemical Fractionation, Coagulants, Erythrocytes, Goats, Metalloproteases, Mice, Inbred BALB C, Plasma, Russell{\textquoteright}s Viper, Toxicity Tests, Acute, Viper Venoms},
	issn = {1879-3150},
	doi = {10.1016/j.toxicon.2015.03.019},
	author = {Thakur, Rupamoni and Chattopadhyay, Pronobesh and Ghosh, Siddharth S and Mukherjee, Ashis K}
}
@article {516,
	title = {A new C-type lectin (RVsnaclec) purified from venom of Daboia russelii russelii shows anticoagulant activity via inhibition of FXa and concentration-dependent differential response to platelets in a Ca{\texttwosuperior}$^{+}$-independent manner. (Mass spectrometry)},
	journal = {Thromb Res},
	volume = {134},
	year = {2014},
	month = {2014 Nov},
	pages = {1150-6},
	abstract = {<p>This is the first report on the characterization of a snaclec (RVsnaclec) purified from Daboia russelii russelii venom. The RVsnaclec is a heterodimer of two subunits, α (15.1 kDa) and β (9 kDa). These subunits are covalently linked to form multimeric (αβ)$_{2}$ and (αβ)$_{4}$ structures. Peptide mass fingerprinting analysis of RVsnaclec via LC-MS/MS demonstrated its similarity to snaclecs purified from other viperid snake venoms. Two tryptic peptide sequences of RVsnaclec revealed the putative conserved domains of C-type lectin (CTL). RVsnaclec dose-dependently increased the Ca-clotting time and prothrombin time of platelet-poor plasma (PPP); however, it did not affect the partial thromboplastin time (APTT) or thrombin time of PPP. The in vitro and in vivo anticoagulant activity of RVsnaclec is correlated to its binding and subsequent uncompetitive inhibition of FXa (Ki = 0.52 μmole) in a Ca(2+)-independent manner; however, supplementation with 0.25 mM Ca(2+) enhanced the Xa binding potency of RVsnaclec. Monovalent or polyvalent antivenom failed to neutralize its anticoagulant potency, and RVsnaclec did not inhibit trypsin, chymotrypsin, thrombin or plasmin. RVsnaclec was devoid of hemolytic activity or cytotoxicity against several human cancer cell lines, demonstrated concentration-dependent aggregation and deaggregation of human platelets, and inhibited the ADP-induced aggregation of platelet. RVsnaclec (5.0 mg/kg body weight) was non-lethal to mice and showed no adverse pharmacological effects, suggesting that it has potential as a lead compound for future therapeutic applications in cardiovascular disorders.</p>
},
	keywords = {Animals, Anticoagulants, Blood Coagulation, Blood Platelets, Calcium, Factor Xa, Factor Xa Inhibitors, Goats, Humans, Lectins, C-Type, Mice, Platelet Aggregation, Russell{\textquoteright}s Viper, Viper Venoms},
	issn = {1879-2472},
	doi = {10.1016/j.thromres.2014.09.009},
	author = {Mukherjee, Ashis K and Dutta, Sumita and Mackessy, Stephen P}
}
