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2cla
From Proteopedia
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|PDB= 2cla |SIZE=350|CAPTION= <scene name='initialview01'>2cla</scene>, resolution 2.35Å | |PDB= 2cla |SIZE=350|CAPTION= <scene name='initialview01'>2cla</scene>, resolution 2.35Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand=CO:COBALT (II) ION'>CO</scene> | + | |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] | + | |ACTIVITY= <span class='plainlinks'>[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] </span> |
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY= | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2cla FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2cla OCA], [http://www.ebi.ac.uk/pdbsum/2cla PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=2cla RCSB]</span> | ||
}} | }} | ||
| Line 26: | Line 29: | ||
[[Category: Leslie, A G.W.]] | [[Category: Leslie, A G.W.]] | ||
[[Category: Moody, P C.E.]] | [[Category: Moody, P C.E.]] | ||
| - | [[Category: CO]] | ||
[[Category: transferase (acyltransferase)]] | [[Category: transferase (acyltransferase)]] | ||
| - | ''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 02:23:03 2008'' |
Revision as of 23:23, 30 March 2008
| |||||||
| , resolution 2.35Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | |||||||
| Activity: | Chloramphenicol O-acetyltransferase, with EC number 2.3.1.28 | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| 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 Mon Mar 31 02:23:03 2008
