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Updated: Jul 31, 2026
13:08
Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
Published on: September 9, 2012
[Interaction of human factor X with thromboplastin]
Biomeditsinskaia Khimiia
|August 27, 2005
Summary
This study reveals that calcium ions (Ca2+) influence factor X binding to tissue thromboplastin, affecting binding site affinity and number. Hydrophobic interactions are key to this calcium-dependent process.
Area of Science:
- Biochemistry
- Molecular Biology
- Hematology
Context:
- Tissue thromboplastin is a key initiator of the extrinsic pathway of blood coagulation.
- Factor X is a crucial serine protease in the coagulation cascade.
- Understanding factor X interactions with thromboplastin is vital for hemostasis research.
Purpose:
- To investigate the binding characteristics of human factor X to tissue thromboplastin.
- To elucidate the role of calcium ions (CaCl2) and divalent cations (EDTA) in this interaction.
- To analyze the impact of thromboplastin proteolysis on factor X binding.
Summary:
- Scatchard analysis identified high and low affinity binding sites for factor X on thromboplastin.
- Calcium removal decreased factor X affinity to high-affinity sites, increasing their number.
- Papain treatment altered affinity and site number, suggesting a role for phospholipids and hydrophobic interactions in Ca2+-dependent binding.
Impact:
- Provides insights into the molecular mechanisms of blood coagulation initiation.
- Highlights the structural and ionic factors governing factor X-thromboplastin interactions.
- Suggests thromboplastin's phospholipid structure dictates binding heterogeneity and influences coagulation dynamics.
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