3cla
From Proteopedia
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| - | [[Image:3cla.gif|left|200px]] | + | [[Image:3cla.gif|left|200px]] |
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| - | '''REFINED CRYSTAL STRUCTURE OF TYPE III CHLORAMPHENICOL ACETYLTRANSFERASE AT 1.75 ANGSTROMS RESOLUTION''' | + | {{Structure |
| + | |PDB= 3cla |SIZE=350|CAPTION= <scene name='initialview01'>3cla</scene>, resolution 1.75Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=CO:COBALT+(II)+ION'>CO</scene> and <scene name='pdbligand=CLM:CHLORAMPHENICOL'>CLM</scene> | ||
| + | |ACTIVITY= [http://en.wikipedia.org/wiki/Chloramphenicol_O-acetyltransferase Chloramphenicol O-acetyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.3.1.28 2.3.1.28] | ||
| + | |GENE= | ||
| + | }} | ||
| + | |||
| + | '''REFINED CRYSTAL STRUCTURE OF TYPE III CHLORAMPHENICOL ACETYLTRANSFERASE AT 1.75 ANGSTROMS RESOLUTION''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 3CLA is a [ | + | 3CLA is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3CLA OCA]. |
==Reference== | ==Reference== | ||
| - | Refined crystal structure of type III chloramphenicol acetyltransferase at 1.75 A resolution., Leslie AG, J Mol Biol. 1990 May 5;213(1):167-86. PMID:[http:// | + | Refined crystal structure of type III chloramphenicol acetyltransferase at 1.75 A resolution., Leslie AG, J Mol Biol. 1990 May 5;213(1):167-86. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/2187098 2187098] |
[[Category: Chloramphenicol O-acetyltransferase]] | [[Category: Chloramphenicol O-acetyltransferase]] | ||
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
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[[Category: transferase (acyltransferase)]] | [[Category: transferase (acyltransferase)]] | ||
| - | ''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 19:04:05 2008'' |
Revision as of 17:04, 20 March 2008
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| , resolution 1.75Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | and | ||||||
| Activity: | Chloramphenicol O-acetyltransferase, with EC number 2.3.1.28 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
REFINED CRYSTAL STRUCTURE OF TYPE III CHLORAMPHENICOL ACETYLTRANSFERASE AT 1.75 ANGSTROMS RESOLUTION
Overview
High level bacterial resistance to chloramphenicol is generally due to O-acetylation of the antibiotic in a reaction catalysed by chloramphenicol acetyltransferase (CAT, EC 2.3.1.28) in which acetyl-coenzyme A is the acyl donor. The crystal structure of the type III enzyme from Escherichia coli with chloramphenicol bound has been determined and refined at 1.75 A resolution, using a restrained parameter reciprocal space least squares procedure. The refined model, which includes chloramphenicol, 204 solvent molecules and two cobalt ions has a crystallographic R-factor of 18.3% for 27,300 reflections between 6 and 1.75 A resolution. The root-mean-square deviation in bond lengths from ideal values is 0.02 A. The cobalt ions play a crucial role in stabilizing the packing of the molecule in the crystal lattice. CAT is a trimer of identical subunits (monomer Mr 25,000) and the trimeric structure is stabilized by a number of hydrogen bonds, some of which result in the extension of a beta-sheet across the subunit interface. Chloramphenicol binds in a deep pocket located at the boundary between adjacent subunits of the trimer, such that the majority of residues forming the binding pocket belong to one subunit while the catalytically essential histidine belongs to the adjacent subunit. His195 is appropriately positioned to act as a general base catalyst in the reaction, and the required tautomeric stabilization is provided by an unusual interaction with a main-chain carbonyl oxygen.
About this Structure
3CLA is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Refined crystal structure of type III chloramphenicol acetyltransferase at 1.75 A resolution., Leslie AG, J Mol Biol. 1990 May 5;213(1):167-86. PMID:2187098
Page seeded by OCA on Thu Mar 20 19:04:05 2008
