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1mkw

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THE CO-CRYSTAL STRUCTURE OF UNLIGANDED BOVINE ALPHA-THROMBIN AND PRETHROMBIN-2: MOVEMENT OF THE YPPW SEGMENT AND ACTIVE SITE RESIDUES UPON LIGAND BINDING

Structural highlights

1mkw is a 3 chain structure with sequence from Bos taurus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 2.3Å
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

THRB_BOVIN Thrombin, which cleaves bonds after Arg and Lys, converts fibrinogen to fibrin and activates factors V, VII, VIII, XIII, and, in complex with thrombomodulin, protein C. Functions in blood homeostasis, inflammation and wound healing (By similarity).

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

Unliganded bovine alpha-thrombin and prethrombin-2 have been co-crystallized, in space group P21212, using either ammonium sulfate or polyethylene glycol 2000 (PEG2K), and their structures determined at 2.2 A and 2.3 A, respectively. Initial phases were determined by molecular replacement and refined using XPLOR to final R factors of 0.187 (Rfree = 0.255) and 0.190 (Rfree = 0.282) for the salt and PEG2K models, respectively. The apo-enzyme form of bovine alpha-thrombin shows dramatic shifts in placement for the Tyr-Pro-Pro-Trp segment, for Glu-192, and for the catalytic residues His-57 and Ser-195, when compared to 4 thrombin complexes representing different states of catalysis, namely (1) the Michaelis complex (residues 7-19 of fibrinogen A alpha with a non-cleavable scissile bond), (2) enzyme-inhibitor complex (D-Phe-Pro-Arg chloromethylketone), (3) enzyme product complex (residues 7-16 of fibrinopeptide A), and (4) the exosite complex (residues 53-64 of hirudin). The structures of bovine and human prethrombin-2 are generally similar to one another (RMS deviation of 0.68 A) but differ significantly in the Arg-15/Ile-16 cleavage region and in the three activation domains, which are disordered in bovine prethrombin-2, analogous to that seen for trypsinogen.

The co-crystal structure of unliganded bovine alpha-thrombin and prethrombin-2: movement of the Tyr-Pro-Pro-Trp segment and active site residues upon ligand binding.,Malkowski MG, Martin PD, Guzik JC, Edwards BF Protein Sci. 1997 Jul;6(7):1438-48. PMID:9232645^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Malkowski MG, Martin PD, Guzik JC, Edwards BF. The co-crystal structure of unliganded bovine alpha-thrombin and prethrombin-2: movement of the Tyr-Pro-Pro-Trp segment and active site residues upon ligand binding. Protein Sci. 1997 Jul;6(7):1438-48. PMID:9232645