Related Experiment Video
Updated: Aug 17, 2026

Characterizing Modulators of Protease-Activated Receptors with a Calcium Mobilization Assay Using a Plate Reader
Published on: May 24, 2024
The intriguing world of prothrombin activators from snake venom
1Protein Science Laboratory, Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543, Singapore. dbskinim@nus.edu.sg
Abstract:
Activation of prothrombin to mature thrombin occurs by the proteolytic action of the prothrombinase complex consisting of a serine proteinase factor Xa, and cofactors factor Va, Ca(2+) ions and phospholipids. Several exogenous prothrombin activators are found in snake venom. They are classified into four groups based on their cofactor requirements. Group A and B prothrombin activators are metalloproteinases whereas group C and D prothrombin activators are serine proteinases. Group C prothrombin activators resemble the mammalian factor Xa-factor Va complex, while Group D activators are structurally and functionally similar to factor Xa. This review provides a detailed description of the current knowledge on all prothrombin activators and highlights several intriguing questions that are yet to be answered.
More Related Videos
10:31A Liposome Membrane Permeability Assay for Investigating the Effects of Phosphatidylinositol Phosphate Groups on Membranotropic Action of Venom PLA2
Published on: September 26, 2025
13:08Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
Published on: September 9, 2012
Related Concept Videos
Anticoagulant Drugs: Low-Molecular-Weight Heparins
Venous Thrombosis III: Interprofessional Care
Extrinsic and Intrinsic Pathways of Hemostasis
The Extrinsic Pathway
The extrinsic pathway of coagulation is typically initiated by tissue damage that exposes blood to tissue factor (TF), a protein released by the damaged tissue cells outside the blood vessels—this interaction with TF triggers biochemical reactions involving specific clotting factors. The key player here is Factor VII, which forms a...
Anticoagulant Drugs: Vitamin K Antagonists and Direct Oral Anticoagulants
Warfarin, a prominent vitamin K antagonist family member, exerts its effect by inhibiting the enzyme VKORC1 (vitamin K epoxide reductase complex 1). By hindering this enzyme, warfarin...
Venous Thrombosis I: Introduction
Coagulation
During the coagulation phase, clotting factors, or procoagulants, play a vital role in initiating and progressing the coagulation cascade. This cascade is a series of reactions...