1xpb
From Proteopedia
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- | [[Image:1xpb.gif|left|200px]] | + | [[Image:1xpb.gif|left|200px]] |
- | + | ||
- | '''STRUCTURE OF BETA-LACTAMASE TEM1''' | + | {{Structure |
+ | |PDB= 1xpb |SIZE=350|CAPTION= <scene name='initialview01'>1xpb</scene>, resolution 1.90Å | ||
+ | |SITE= <scene name='pdbsite=ACT:Active+Site'>ACT</scene> | ||
+ | |LIGAND= <scene name='pdbligand=SO4:SULFATE ION'>SO4</scene> | ||
+ | |ACTIVITY= [http://en.wikipedia.org/wiki/Beta-lactamase Beta-lactamase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.5.2.6 3.5.2.6] | ||
+ | |GENE= | ||
+ | }} | ||
+ | |||
+ | '''STRUCTURE OF BETA-LACTAMASE TEM1''' | ||
+ | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
- | 1XPB is a [ | + | 1XPB 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=1XPB OCA]. |
==Reference== | ==Reference== | ||
- | TEM1 beta-lactamase structure solved by molecular replacement and refined structure of the S235A mutant., Fonze E, Charlier P, To'th Y, Vermeire M, Raquet X, Dubus A, Frere JM, Acta Crystallogr D Biol Crystallogr. 1995 Sep 1;51(Pt 5):682-94. PMID:[http:// | + | TEM1 beta-lactamase structure solved by molecular replacement and refined structure of the S235A mutant., Fonze E, Charlier P, To'th Y, Vermeire M, Raquet X, Dubus A, Frere JM, Acta Crystallogr D Biol Crystallogr. 1995 Sep 1;51(Pt 5):682-94. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/15299797 15299797] |
[[Category: Beta-lactamase]] | [[Category: Beta-lactamase]] | ||
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
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[[Category: transposable element]] | [[Category: transposable element]] | ||
- | ''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 15:12:46 2008'' |
Revision as of 13:12, 20 March 2008
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, resolution 1.90Å | |||||||
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Sites: | |||||||
Ligands: | |||||||
Activity: | Beta-lactamase, with EC number 3.5.2.6 | ||||||
Coordinates: | save as pdb, mmCIF, xml |
STRUCTURE OF BETA-LACTAMASE TEM1
Overview
beta-Lactamases are bacterial enzymes which catalyse the hydrolysis of the beta-lactam ring of penicillins, cephalosporins and related compounds, thus inactivating these antibiotics. The crystal structure of the TEM1 beta-lactamase has been determined at 1.9 A resolution by the molecular-replacement method, using the atomic coordinates of two homologous beta-lactamase refined structures which show about 36% strict identity in their amino-acid sequences and 1.96 A r.m.s. deviation between equivalent Calpha atoms. The TEM1 enzyme crystallizes in space group P2(1)2(1)2(1) and there is one molecule per asymmetric unit. The structure was refined by simulated annealing to an R-factor of 15.6% for 15 086 reflections with I >/= 2sigma(I) in the resolution range 5.0-1.9 A. The final crystallographic structure contains 263 amino-acid residues, one sulfate anion in the catalytic cleft and 135 water molecules per asymmetric unit. The folding is very similar to that of the other known class A beta-lactamases. It consists of two domains, the first is formed by a five-stranded beta-sheet covered by three alpha-helices on one face and one alpha-helix on the other, the second domain contains mainly alpha-helices. The catalytic cleft is located at the interface between the two domains. We also report the crystallographic study of the TEM S235A mutant. This mutation of an active-site residue specifically decreases the acylation rate of cephalosporins. This TEM S235A mutant crystallizes under the same conditions as the wild-type protein and its structure was refined at 2.0 A resolution with an R value of 17.6%. The major modification is the appearance of a water molecule near the mutated residue, which is incompatible with the OG 235 present in the wild-type enzyme, and causes very small perturbations in the interaction network in the active site.
About this Structure
1XPB is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
TEM1 beta-lactamase structure solved by molecular replacement and refined structure of the S235A mutant., Fonze E, Charlier P, To'th Y, Vermeire M, Raquet X, Dubus A, Frere JM, Acta Crystallogr D Biol Crystallogr. 1995 Sep 1;51(Pt 5):682-94. PMID:15299797
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