1dy6
From Proteopedia
| Line 5: | Line 5: | ||
|SITE= <scene name='pdbsite=ASA:Beta-Lactam+Binding+Site,+Chain+A'>ASA</scene> and <scene name='pdbsite=ASB:Beta-Lactam+Binding+Site,+Chain+B'>ASB</scene> | |SITE= <scene name='pdbsite=ASA:Beta-Lactam+Binding+Site,+Chain+A'>ASA</scene> and <scene name='pdbsite=ASB:Beta-Lactam+Binding+Site,+Chain+B'>ASB</scene> | ||
|LIGAND= | |LIGAND= | ||
| - | |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] | + | |ACTIVITY= <span class='plainlinks'>[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] </span> |
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY= | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1dy6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1dy6 OCA], [http://www.ebi.ac.uk/pdbsum/1dy6 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1dy6 RCSB]</span> | ||
}} | }} | ||
| Line 37: | Line 40: | ||
[[Category: lactamase]] | [[Category: lactamase]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 19:51:09 2008'' |
Revision as of 16:51, 30 March 2008
| |||||||
| , resolution 2.13Å | |||||||
|---|---|---|---|---|---|---|---|
| Sites: | and | ||||||
| Activity: | Beta-lactamase, with EC number 3.5.2.6 | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
STRUCTURE OF THE IMIPENEM-HYDROLYZING BETA-LACTAMASE SME-1
Overview
The structure of the beta-lactamase SME-1 from Serratia marcescens, a class A enzyme characterized by its significant activity against imipenem, has been determined to 2.13 A resolution. The overall structure of SME-1 is similar to that of other class A beta-lactamases. In the active-site cavity, most of the residues found in SME-1 are conserved among class A beta-lactamases, except at positions 104, 105 and 237, where a tyrosine, a histidine and a serine are found, respectively, and at position 238, which is occupied by a cysteine forming a disulfide bridge with the other cysteine residue located at position 69. The crucial role played by this disulfide bridge in SME-1 was confirmed by site-directed mutagenesis of Cys69 to Ala, which resulted in a mutant unable to confer resistance to imipenem and all other beta-lactam antibiotics tested. Another striking structural feature found in SME-1 was the short distance separating the side chains of the active serine residue at position 70 and the strictly conserved glutamate at position 166, which is up to 1.4 A shorter in SME-1 compared with other class A beta-lactamases. Consequently, the SME-1 structure cannot accommodate the essential catalytic water molecule found between Ser70 and Glu166 in the other class A beta-lactamases described so far, suggesting that a significant conformational change may be necessary in SME-1 to properly position the hydrolytic water molecule involved in the hydrolysis of the acyl-enzyme intermediate.
About this Structure
1DY6 is a Single protein structure of sequence from Serratia marcescens. Full crystallographic information is available from OCA.
Reference
Structure of the imipenem-hydrolyzing class A beta-lactamase SME-1 from Serratia marcescens., Sougakoff W, L'Hermite G, Pernot L, Naas T, Guillet V, Nordmann P, Jarlier V, Delettre J, Acta Crystallogr D Biol Crystallogr. 2002 Feb;58(Pt 2):267-74. Epub 2002, Jan 24. PMID:11807251
Page seeded by OCA on Sun Mar 30 19:51:09 2008
