1vit
From Proteopedia
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THROMBIN:HIRUDIN 51-65 COMPLEX
Overview
Crystals of the bovine thrombin-hirudins(51-65) complex have space group, P6(1)22 with cell constants a = 116.4, and c = 200.6 A and two thrombin, molecules in the asymmetric unit. Only one thrombin molecule could be, located by generalized molecular replacement; the second was fit visually, as a rigid body to an improved electron-density difference map. The, structure was refined to R = 0.192 with two B values per residue (main, chain and side chain) at 3.2 A. The polar interactions of the peptides, with the exosite of thrombin show differences consistent with the known, flexibility in the interactions of the C-terminal peptide of hirudin with, thrombin. The hirudin peptide in complex 2 has a higher temperature factor, as compared with peptide 1 which may be correlated partly with a larger, number of short-range electrostatic interactions between peptide 1 and, thrombin and partly with the fact that thrombin 2 is epsilon-thrombin, which is cleaved at Thr149A near the peptide binding site. Later, using, this structure as a test case, it was shown that the position for the, second thrombin could also be determined by a novel modification of the, molecular-replacement method in which the contribution of the known, molecule is subtracted from the structure factors. This approach is facile, and applicable to any crystal containing two or more macromolecules in the, asymmetric unit in which some but not all of the molecules can be, determined by molecular replacement.
About this Structure
1VIT is a Protein complex structure of sequences from Bos taurus with NAG as ligand. Active as Thrombin, with EC number 3.4.21.5 Full crystallographic information is available from OCA.
Reference
Structure of a bovine thrombin-hirudin51-65 complex determined by a combination of molecular replacement and graphics. Incorporation of known structural information in molecular replacement., Vitali J, Martin PD, Malkowski MG, Olsen CM, Johnson PH, Edwards BF, Acta Crystallogr D Biol Crystallogr. 1996 May 1;52(Pt 3):453-64. PMID:15299666
Page seeded by OCA on Wed Nov 21 04:53:29 2007
