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4cha
From Proteopedia
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STRUCTURE OF ALPHA-*CHYMOTRYPSIN REFINED AT 1.68 ANGSTROMS RESOLUTION
Overview
Diffraction data for alpha-chymotrypsin crystals at -10 degrees C were, measured at 1.68 A resolution and refined by restrained structure-factor, least-squares refinement. The two independent chymotrypsin molecules in, the crystallographic asymmetric unit were refined independently. The, overall structure of alpha-chymotrypsin is little changed from published, co-ordinates. The root-mean-square shift of C alpha co-ordinates is 0.42, A, co-ordinates for the two molecules showing a root-mean-square, difference of 0.19 A. Certain regions with high disorder (residues 9 to, 14, 73 to 79) remain difficult to interpret and several side-chains are, disordered. Some water molecule positions have been changed. The absence, of the tosyl group has made a significant difference to the refined, structure at the active site. This now agrees closely with other enzymes, of the trypsin family that have been refined at high resolution. There is, a strong hydrogen bond between N epsilon 2 (His57) and O gamma (Ser195) in, the free enzyme, in line with the published description of the charge, relay system.
About this Structure
4CHA is a Protein complex structure of sequences from Bos taurus. Active as Chymotrypsin, with EC number 3.4.21.1 Full crystallographic information is available from OCA.
Reference
Structure of alpha-chymotrypsin refined at 1.68 A resolution., Tsukada H, Blow DM, J Mol Biol. 1985 Aug 20;184(4):703-11. PMID:4046030
Page seeded by OCA on Tue Nov 20 19:28:49 2007
