1UJ3
Crystal structure of a humanized Fab fragment of anti-tissue-factor antibody in complex with tissue factor
Summary for 1UJ3
Entry DOI | 10.2210/pdb1uj3/pdb |
Descriptor | IgG Fab light chain, IgG Fab heavy chain, tissue factor, ... (4 entities in total) |
Functional Keywords | tissue factor, antigen, antibody, fab, immune system-blood clotting complex, immune system/blood clotting |
Biological source | Homo sapiens (human) More |
Total number of polymer chains | 3 |
Total formula weight | 70034.92 |
Authors | Ohto, U.,Mizutani, R.,Nakamura, M.,Adachi, H.,Satow, Y. (deposition date: 2003-07-25, release date: 2004-07-25, Last modification date: 2024-10-16) |
Primary citation | Ohto, U.,Mizutani, R.,Nakamura, M.,Adachi, H.,Satow, Y. Crystal structure of a humanized Fab fragment of anti-tissue-factor antibody in complex with tissue factor. J.Synchrotron Radiat., 11:105-108, 2004 Cited by PubMed Abstract: Tissue factor (TF) is a membrane-anchored protein that initiates the extrinsic cascade of blood coagulation. TF forms a complex with serine protease Factor VIIa, and then activates Factor X zymogen to Factor Xa, leading to the blood coagulation. Humanized anti-TF antibody hATR-5 strongly inhibits TF-initiated blood coagulation, and is of potential use for various thrombotic diseases. The Fab fragment of antibody hATR-5 is obtained for crystallization. The crystal structure of the complex of the Fab with extracellular domains of human TF was determined with the molecular replacement method, and refined to an R factor of 0.196 at 2.1 A resolution. All the complementarity-determining regions (CDRs) of the Fab are involved in interaction with the C-terminal-side extracellular domain of TF through 19 hydrogen bonds. The interface between the Fab and TF molecules contains 15 water molecules, and yields buried surface areas as wide as 2000 A2. The TF surface in the interface is possibly involved in the activation of Factor X, by forming a transient ternary complex of Factor X-TF-Factor VIIa. Electrostatic interactions are predominantly observed between the heavy-chain CDRs and TF. These hydrogen-bonding and electrostatic interactions together with the wide buried areas contribute to the high affinity of the antibody toward TF, leading to the effective inhibition of the TF-initiated blood coagulation. PubMed: 14646147DOI: 10.1107/s0909049503023513 PDB entries with the same primary citation |
Experimental method | X-RAY DIFFRACTION (2.1 Å) |
Structure validation
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