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1i2s
From Proteopedia
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| - | [[Image:1i2s.jpg|left|200px]] | + | [[Image:1i2s.jpg|left|200px]] |
| - | + | ||
| - | '''BETA-LACTAMASE FROM BACILLUS LICHENIFORMIS BS3''' | + | {{Structure |
| + | |PDB= 1i2s |SIZE=350|CAPTION= <scene name='initialview01'>1i2s</scene>, resolution 1.70Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=NA:SODIUM+ION'>NA</scene> and <scene name='pdbligand=CIT:CITRIC ACID'>CIT</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= | ||
| + | }} | ||
| + | |||
| + | '''BETA-LACTAMASE FROM BACILLUS LICHENIFORMIS BS3''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1I2S is a [ | + | 1I2S is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_licheniformis Bacillus licheniformis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1I2S OCA]. |
==Reference== | ==Reference== | ||
| - | Crystal structures of the Bacillus licheniformis BS3 class A beta-lactamase and of the acyl-enzyme adduct formed with cefoxitin., Fonze E, Vanhove M, Dive G, Sauvage E, Frere JM, Charlier P, Biochemistry. 2002 Feb 12;41(6):1877-85. PMID:[http:// | + | Crystal structures of the Bacillus licheniformis BS3 class A beta-lactamase and of the acyl-enzyme adduct formed with cefoxitin., Fonze E, Vanhove M, Dive G, Sauvage E, Frere JM, Charlier P, Biochemistry. 2002 Feb 12;41(6):1877-85. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/11827533 11827533] |
[[Category: Bacillus licheniformis]] | [[Category: Bacillus licheniformis]] | ||
[[Category: Beta-lactamase]] | [[Category: Beta-lactamase]] | ||
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[[Category: serine beta-lactamase]] | [[Category: serine beta-lactamase]] | ||
| - | ''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 11:44:46 2008'' |
Revision as of 09:44, 20 March 2008
| |||||||
| , resolution 1.70Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | and | ||||||
| Activity: | Beta-lactamase, with EC number 3.5.2.6 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
BETA-LACTAMASE FROM BACILLUS LICHENIFORMIS BS3
Overview
The Bacillus licheniformis BS3 beta-lactamase catalyzes the hydrolysis of the beta-lactam ring of penicillins, cephalosporins, and related compounds. The production of beta-lactamases is the most common and thoroughly studied cause of antibiotic resistance. Although they escape the hydrolytic activity of the prototypical Staphylococcus aureus beta-lactamase, many cephems are good substrates for a large number of beta-lactamases. However, the introduction of a 7alpha-methoxy substituent, as in cefoxitin, extends their antibacterial spectrum to many cephalosporin-resistant Gram-negative bacteria. The 7alpha-methoxy group selectively reduces the hydrolytic action of many beta-lactamases without having a significant effect on the affinity for the target enzymes, the membrane penicillin-binding proteins. We report here the crystallographic structures of the BS3 enzyme and its acyl-enzyme adduct with cefoxitin at 1.7 A resolution. The comparison of the two structures reveals a covalent acyl-enzyme adduct with perturbed active site geometry, involving a different conformation of the omega-loop that bears the essential catalytic Glu166 residue. This deformation is induced by the cefoxitin side chain whose position is constrained by the presence of the alpha-methoxy group. The hydrolytic water molecule is also removed from the active site by the 7beta-carbonyl of the acyl intermediate. In light of the interactions and steric hindrances in the active site of the structure of the BS3-cefoxitin acyl-enzyme adduct, the crucial role of the conserved Asn132 residue is confirmed and a better understanding of the kinetic results emerges.
About this Structure
1I2S is a Single protein structure of sequence from Bacillus licheniformis. Full crystallographic information is available from OCA.
Reference
Crystal structures of the Bacillus licheniformis BS3 class A beta-lactamase and of the acyl-enzyme adduct formed with cefoxitin., Fonze E, Vanhove M, Dive G, Sauvage E, Frere JM, Charlier P, Biochemistry. 2002 Feb 12;41(6):1877-85. PMID:11827533
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