4wbc
From Proteopedia
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2.13 A STRUCTURE OF A KUNITZ-TYPE WINGED BEAN CHYMOTRYPSIN INHIBITOR PROTEIN
Overview
The crystal structure of a Kunitz-type double-headed alpha--chymotrypsin, inhibitor from winged bean seeds has been refined at 2.13 A resolution, using data collected from cryo-cooled (90 K) crystals which belong to the, hexagonal space group P6(1)22 with unit-cell parameters a = b = 60.84, c =, 207.91 A. The volume of the unit cell is reduced by 5.3% on cooling. The, refinement converged to an R value of 20.0% (R(free) = 25.8%) for 11100, unique reflections and the model shows good stereochemistry, with r.m.s., deviations from ideal values for bond lengths and bond angles of 0.011 A, and 1.4 degrees, respectively. The structural architecture of the protein, consists of 12 antiparallel beta-strands joined in the form of a, characteristic beta-trefoil fold, with the two reactive-site regions, Asn38-Leu43 and Gln63-Phe68, situated on two external loops. Although the, overall protein fold is the same as that of the room-temperature model, some conformational changes are observed in the loop regions and in the, side chains of a few surface residues. A total of 176 ordered water, molecules and five sulfate ions are included in the model.
About this Structure
4WBC is a Single protein structure of sequence from Psophocarpus tetragonolobus with SO4 as ligand. This structure superseeds the now removed PDB entry 3WBC. Full crystallographic information is available from OCA.
Reference
Cryocrystallography of a Kunitz-type serine protease inhibitor: the 90 K structure of winged bean chymotrypsin inhibitor (WCI) at 2.13 A resolution., Ravichandran S, Sen U, Chakrabarti C, Dattagupta JK, Acta Crystallogr D Biol Crystallogr. 1999 Nov;55(Pt 11):1814-21. PMID:10531477
Page seeded by OCA on Tue Nov 20 19:51:41 2007
