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2cla
From Proteopedia
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| - | [[Image:2cla.jpg|left|200px]] | + | [[Image:2cla.jpg|left|200px]] |
| - | + | ||
| - | '''CRYSTAL STRUCTURE OF THE ASP-199-ASN MUTANT OF CHLORAMPHENICOL ACETYLTRANSFERASE TO 2.35 ANGSTROMS RESOLUTION. STRUCTURAL CONSEQUENCES OF DISRUPTION OF A BURIED SALT-BRIDGE''' | + | {{Structure |
| + | |PDB= 2cla |SIZE=350|CAPTION= <scene name='initialview01'>2cla</scene>, resolution 2.35Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=CO:COBALT (II) ION'>CO</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= | ||
| + | }} | ||
| + | |||
| + | '''CRYSTAL STRUCTURE OF THE ASP-199-ASN MUTANT OF CHLORAMPHENICOL ACETYLTRANSFERASE TO 2.35 ANGSTROMS RESOLUTION. STRUCTURAL CONSEQUENCES OF DISRUPTION OF A BURIED SALT-BRIDGE''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 2CLA is a [ | + | 2CLA 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=2CLA OCA]. |
==Reference== | ==Reference== | ||
| - | Crystal structure of the aspartic acid-199----asparagine mutant of chloramphenicol acetyltransferase to 2.35-A resolution: structural consequences of disruption of a buried salt bridge., Gibbs MR, Moody PC, Leslie AG, Biochemistry. 1990 Dec 25;29(51):11261-5. PMID:[http:// | + | Crystal structure of the aspartic acid-199----asparagine mutant of chloramphenicol acetyltransferase to 2.35-A resolution: structural consequences of disruption of a buried salt bridge., Gibbs MR, Moody PC, Leslie AG, Biochemistry. 1990 Dec 25;29(51):11261-5. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/2271709 2271709] |
[[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 16:16:52 2008'' |
Revision as of 14:16, 20 March 2008
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| , resolution 2.35Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | |||||||
| Activity: | Chloramphenicol O-acetyltransferase, with EC number 2.3.1.28 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
CRYSTAL STRUCTURE OF THE ASP-199-ASN MUTANT OF CHLORAMPHENICOL ACETYLTRANSFERASE TO 2.35 ANGSTROMS RESOLUTION. STRUCTURAL CONSEQUENCES OF DISRUPTION OF A BURIED SALT-BRIDGE
Overview
The crystal structure of the Asp-199----Asn mutant of chloramphenicol acetyltransferase (CAT) has been determined to 2.35-A resolution. In wild-type CAT Asp-199 is involved in a fully buried intrasubunit salt bridge with Arg-18, an interaction that is adjacent to the active site. Replacement of aspartate with asparagine by site-directed mutagenesis disrupts this salt bridge and causes extensive conformational changes within the active site. The imidazole group of the catalytically essential His-195 is reoriented, with the loss of interactions thought to stabilize the preferred tautomer of this residue. Arg-18 and Asn-199 form three new intersubunit interactions as a result of large side-chain torsion angle changes which cause the movement of two polypeptide loops, some residues of which are up to 20 A away from the site of the mutation. The new interactions of Arg-18 and Asn-199 compensate for the loss of the buried salt bridge and afford near-wild-type thermostability to Asn-199 CAT, albeit with a greatly reduced activity.
About this Structure
2CLA is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Crystal structure of the aspartic acid-199----asparagine mutant of chloramphenicol acetyltransferase to 2.35-A resolution: structural consequences of disruption of a buried salt bridge., Gibbs MR, Moody PC, Leslie AG, Biochemistry. 1990 Dec 25;29(51):11261-5. PMID:2271709
Page seeded by OCA on Thu Mar 20 16:16:52 2008
