1bth
From Proteopedia
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| , resolution 2.3Å | |||||||
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| Activity: | Thrombin, with EC number 3.4.21.5 | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
STRUCTURE OF THROMBIN COMPLEXED WITH BOVINE PANCREATIC TRYPSIN INHIBITOR
Overview
Previous crystal structures of thrombin indicate that the 60-insertion loop is a rigid moiety that partially occludes the active site, suggesting that this structural feature plays a decisive role in restricting thrombin's specificity. This restricted specificity is typified by the experimental observation that thrombin is not inhibited by micromolar concentrations of basic pancreatic trypsin inhibitor (BPTI). Surprisingly, a single atom mutation in thrombin (E192Q) results in a 10(-8) M affinity for BPTI. The crystal structure of human thrombin mutant E192Q has been solved in complex with BPTI at 2.3 A resolution. Binding of the Kunitz inhibitor is accompanied by gross structural rearrangements in thrombin. In particular, thrombin's 60-loop is found in a significantly different conformation. Concomitant reorganization of other surface loops that surround the active site, i.e. the 37-loop, the 148-loop and the 99-loop, is observed. Thrombin can therefore undergo major structural reorganization upon strong ligand binding. Implications for the interaction of thrombin with antithrombin and thrombomodulin are discussed.
About this Structure
1BTH is a Protein complex structure of sequences from Bos taurus. Full crystallographic information is available from OCA.
Reference
The thrombin E192Q-BPTI complex reveals gross structural rearrangements: implications for the interaction with antithrombin and thrombomodulin., van de Locht A, Bode W, Huber R, Le Bonniec BF, Stone SR, Esmon CT, Stubbs MT, EMBO J. 1997 Jun 2;16(11):2977-84. PMID:9214615
Page seeded by OCA on Sun Mar 30 19:07:59 2008
