1bc2: Difference between revisions
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
[[Image:1bc2.gif|left|200px]] | [[Image:1bc2.gif|left|200px]] | ||
'''ZN-DEPENDENT METALLO-BETA-LACTAMASE FROM BACILLUS CEREUS''' | {{Structure | ||
|PDB= 1bc2 |SIZE=350|CAPTION= <scene name='initialview01'>1bc2</scene>, resolution 1.9Å | |||
|SITE= <scene name='pdbsite=ASA:Strained+Buried+Residue,+Close+To+Active+Site+In+Molecule+A'>ASA</scene>, <scene name='pdbsite=ASB:Strained+Buried+Residue,+Close+To+Active+Site+In+Molecule+B'>ASB</scene>, <scene name='pdbsite=ZNA:Zn+Binding+Sites+And+Active+Site+For+Molecule+A'>ZNA</scene> and <scene name='pdbsite=ZNB:Zn+Binding+Sites+And+Active+Site+For+Molecule+B'>ZNB</scene> | |||
|LIGAND= <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene> and <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= | |||
}} | |||
'''ZN-DEPENDENT METALLO-BETA-LACTAMASE FROM BACILLUS CEREUS''' | |||
==Overview== | ==Overview== | ||
| Line 7: | Line 16: | ||
==About this Structure== | ==About this Structure== | ||
1BC2 is a [ | 1BC2 is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_cereus Bacillus cereus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1BC2 OCA]. | ||
==Reference== | ==Reference== | ||
Crystal structure of the zinc-dependent beta-lactamase from Bacillus cereus at 1.9 A resolution: binuclear active site with features of a mononuclear enzyme., Fabiane SM, Sohi MK, Wan T, Payne DJ, Bateson JH, Mitchell T, Sutton BJ, Biochemistry. 1998 Sep 8;37(36):12404-11. PMID:[http:// | Crystal structure of the zinc-dependent beta-lactamase from Bacillus cereus at 1.9 A resolution: binuclear active site with features of a mononuclear enzyme., Fabiane SM, Sohi MK, Wan T, Payne DJ, Bateson JH, Mitchell T, Sutton BJ, Biochemistry. 1998 Sep 8;37(36):12404-11. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/9730812 9730812] | ||
[[Category: Bacillus cereus]] | [[Category: Bacillus cereus]] | ||
[[Category: Beta-lactamase]] | [[Category: Beta-lactamase]] | ||
| Line 23: | Line 32: | ||
[[Category: penicillinase]] | [[Category: penicillinase]] | ||
''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 10:08:59 2008'' | ||
Revision as of 11:09, 20 March 2008
| |||||||
| , resolution 1.9Å | |||||||
|---|---|---|---|---|---|---|---|
| Sites: | , , and | ||||||
| Ligands: | and | ||||||
| Activity: | Beta-lactamase, with EC number 3.5.2.6 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
ZN-DEPENDENT METALLO-BETA-LACTAMASE FROM BACILLUS CEREUS
OverviewOverview
The structure of the zinc-dependent beta-lactamase II from Bacillus cereus has been determined at 1.9 A resolution in a crystal form with two molecules in the asymmetric unit and 400 waters (space group P3121; Rcryst = 20.8%). The active site contains two zinc ions: Zn1 is tightly coordinated by His86, His88, and His149, while Zn2 is loosely coordinated by Asp90, Cys168, and His210. A water molecule (W1) lies between the two zinc ions but is significantly closer to Zn1 and at a distance of only 1.9 A is effectively a hydroxide moiety and a potential, preactivated nucleophile. In fact, Asp90 bridges W1 to Zn2, and its location is thus distinct from that of the bridging water molecules in the binuclear zinc peptidases or other binuclear zinc hydrolases. Modeling of penicillin, cephalosporin, and carbapenem binding shows that all are readily accommodated within the shallow active site cleft of the enzyme, and the Zn1-bound hydroxide is ideally located for nucleophilic attack at the beta-lactam carbonyl. This enzyme also functions with only one zinc ion present. The Zn1-Zn2 distances differ in the two independent molecules in the crystal (3.9 and 4.4 A), yet the Zn1-W1 distances are both 1.9 A, arguing against involvement of Zn2 in W1 activation. The role of Zn2 is unclear, but the B. cereus enzyme may be an evolutionary intermediate between the mono- and bizinc metallo-beta-lactamases. The broad specificity of this enzyme, together with the increasing prevalence of zinc-dependent metallo-beta-lactamases, poses a real clinical threat, and this structure provides a basis for understanding its mechanism and designing inhibitors.
About this StructureAbout this Structure
1BC2 is a Single protein structure of sequence from Bacillus cereus. Full crystallographic information is available from OCA.
ReferenceReference
Crystal structure of the zinc-dependent beta-lactamase from Bacillus cereus at 1.9 A resolution: binuclear active site with features of a mononuclear enzyme., Fabiane SM, Sohi MK, Wan T, Payne DJ, Bateson JH, Mitchell T, Sutton BJ, Biochemistry. 1998 Sep 8;37(36):12404-11. PMID:9730812
Page seeded by OCA on Thu Mar 20 10:08:59 2008