6cha: Difference between revisions
No edit summary |
No edit summary |
||
Line 4: | Line 4: | ||
|PDB= 6cha |SIZE=350|CAPTION= <scene name='initialview01'>6cha</scene>, resolution 1.8Å | |PDB= 6cha |SIZE=350|CAPTION= <scene name='initialview01'>6cha</scene>, resolution 1.8Å | ||
|SITE= | |SITE= | ||
|LIGAND= <scene name='pdbligand=PBA:PHENYLETHANE BORONIC ACID'>PBA</scene> | |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] | |ACTIVITY= <span class='plainlinks'>[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] </span> | ||
|GENE= | |GENE= | ||
|DOMAIN= | |||
|RELATEDENTRY= | |||
|RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6cha FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6cha OCA], [http://www.ebi.ac.uk/pdbsum/6cha PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=6cha RCSB]</span> | |||
}} | }} | ||
Line 25: | Line 28: | ||
[[Category: Blevins, R A.]] | [[Category: Blevins, R A.]] | ||
[[Category: Tulinsky, A.]] | [[Category: Tulinsky, A.]] | ||
[[Category: hydrolase (serine proteinase)]] | [[Category: hydrolase (serine proteinase)]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Mar 31 05:42:44 2008'' |
Revision as of 05:42, 31 March 2008
| |||||||
, resolution 1.8Å | |||||||
---|---|---|---|---|---|---|---|
Ligands: | |||||||
Activity: | Chymotrypsin, with EC number 3.4.21.1 | ||||||
Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
Coordinates: | save as pdb, mmCIF, xml |
STRUCTURE OF A TETRAHEDRAL TRANSITION STATE COMPLEX OF ALPHA-*CHYMOTRYPSIN AT 1.8-*ANGSTROMS RESOLUTION
OverviewOverview
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 StructureAbout this Structure
6CHA is a Protein complex structure of sequences from Bos taurus. Full crystallographic information is available from OCA.
ReferenceReference
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
Page seeded by OCA on Mon Mar 31 05:42:44 2008