6cha
From Proteopedia
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| - | [[Image:6cha.gif|left|200px]] | + | [[Image:6cha.gif|left|200px]] |
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| - | '''STRUCTURE OF A TETRAHEDRAL TRANSITION STATE COMPLEX OF ALPHA-*CHYMOTRYPSIN AT 1.8-*ANGSTROMS RESOLUTION''' | + | {{Structure |
| + | |PDB= 6cha |SIZE=350|CAPTION= <scene name='initialview01'>6cha</scene>, resolution 1.8Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=PBA:PHENYLETHANE BORONIC ACID'>PBA</scene> | ||
| + | |ACTIVITY= [http://en.wikipedia.org/wiki/Chymotrypsin Chymotrypsin], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.21.1 3.4.21.1] | ||
| + | |GENE= | ||
| + | }} | ||
| + | |||
| + | '''STRUCTURE OF A TETRAHEDRAL TRANSITION STATE COMPLEX OF ALPHA-*CHYMOTRYPSIN AT 1.8-*ANGSTROMS RESOLUTION''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 6CHA is a [ | + | 6CHA is a [[Protein complex]] structure of sequences from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6CHA OCA]. |
==Reference== | ==Reference== | ||
| - | Structure of a tetrahedral transition state complex of alpha-chymotrypsin dimer at 1.8-A resolution., Tulinsky A, Blevins RA, J Biol Chem. 1987 Jun 5;262(16):7737-43. PMID:[http:// | + | Structure of a tetrahedral transition state complex of alpha-chymotrypsin dimer at 1.8-A resolution., Tulinsky A, Blevins RA, J Biol Chem. 1987 Jun 5;262(16):7737-43. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/3584139 3584139] |
[[Category: Bos taurus]] | [[Category: Bos taurus]] | ||
[[Category: Chymotrypsin]] | [[Category: Chymotrypsin]] | ||
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[[Category: hydrolase (serine proteinase)]] | [[Category: hydrolase (serine proteinase)]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 19:13:15 2008'' |
Revision as of 17:13, 20 March 2008
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| , resolution 1.8Å | |||||||
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| Ligands: | |||||||
| Activity: | Chymotrypsin, with EC number 3.4.21.1 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
STRUCTURE OF A TETRAHEDRAL TRANSITION STATE COMPLEX OF ALPHA-*CHYMOTRYPSIN AT 1.8-*ANGSTROMS RESOLUTION
Overview
A 1.8-A resolution x-ray crystallographic restrained least squares refinement has been carried out on the phenylethane boronic acid (PEBA) complex of alpha-chymotrypsin dimer (alpha-CHT), and it has been compared to the 1.67-A resolution structure of the native enzyme. PEBA has a high binding affinity for alpha-CHT, and the boronate forms a tetrahedral complex with Ser-195 OG of one molecule of the dimer; the boronate in the other molecule is severely disordered and does not form a tetrahedral complex. The former could be a model of the transition state of catalysis. The complex of PEBA X alpha-CHT displays significant nonequivalence in conformation of side chains between the independent molecules comparable to the native enzyme, but, like the latter, shows a high degree of fidelity in the folding of the main chain. The orientation of the phenyl ring, CA and CB of PEBA, in the specificity sites of the two molecules is similar, suggesting that recognition is fairly insensitive to small departures from local symmetry; the same does not apply to the boronate functionalities suggesting that greater precision is required for catalysis. The folding of the molecule remains the same upon PEBA binding, but some of the side chains respond nonequivalently. The latter is a consequence of the inherent nonequivalence of the native dimer and the asymmetrical nature of the PEBA binding.
About this Structure
6CHA is a Protein complex structure of sequences from Bos taurus. Full crystallographic information is available from OCA.
Reference
Structure of a tetrahedral transition state complex of alpha-chymotrypsin dimer at 1.8-A resolution., Tulinsky A, Blevins RA, J Biol Chem. 1987 Jun 5;262(16):7737-43. PMID:3584139
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