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1xx2

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Revision as of 14:13, 10 September 2015

Refinement of P99 beta-lactamase from Enterobacter cloacae

Structural highlights

1xx2 is a 2 chain structure with sequence from Enterobacter cloacae. This structure supersedes the now removed PDB entry 2blt. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Related:	1bls, 2blt
Activity:	Beta-lactamase, with EC number 3.5.2.6
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum

Function

[AMPC_ENTCL] This protein is a serine beta-lactamase with a substrate specificity for cephalosporins.

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

The structure of the class C ampC beta-lactamase (cephalosporinase) from Enterobacter cloacae strain P99 has been established by x-ray crystallography to 2-A resolution and compared to a class A beta-lactamase (penicillinase) structure. The binding site for beta-lactam (penicillinase) structure. The binding site for beta-lactam antibiotics is generally more open than that in penicillinases, in agreement with the ability of the class C beta-lactamases to better bind third-generation cephalosporins. Four corresponding catalytic residues (Ser-64/70, Lys-67/73, Lys-315/234, and Tyr-150/Ser-130 in class C/A) lie in equivalent positions within 0.4 A. Significant differences in positions and accessibilities of Arg-349/244 may explain the inability of clavulanate-type inhibitors to effectively inactivate the class C beta-lactamases. Glu-166, required for deacylation of the beta-lactamoyl intermediate in class A penicillinases, has no counterpart in this cephalosporinase; the nearest candidate, Asp-217, is 10 A from the reactive Ser-64. A comparison of overall tertiary folding shows that the cephalosporinase, more than the penicillinase, is broadly similar to the ancestral beta-lactam-inhibited enzymes of bacterial cell wall synthesis. On this basis, it is proposed that the cephalosporinase is the older of the two beta-lactamases, and, therefore, that a local refolding in the active site, rather than a simple point mutation, was required for the primordial class C beta-lactamase to evolve to the class A beta-lactamase having an improved ability to catalyze the deacylation step of beta-lactam hydrolysis.

Evolution of an enzyme activity: crystallographic structure at 2-A resolution of cephalosporinase from the ampC gene of Enterobacter cloacae P99 and comparison with a class A penicillinase.,Lobkovsky E, Moews PC, Liu H, Zhao H, Frere JM, Knox JR Proc Natl Acad Sci U S A. 1993 Dec 1;90(23):11257-61. PMID:8248237^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Lobkovsky E, Moews PC, Liu H, Zhao H, Frere JM, Knox JR. Evolution of an enzyme activity: crystallographic structure at 2-A resolution of cephalosporinase from the ampC gene of Enterobacter cloacae P99 and comparison with a class A penicillinase. Proc Natl Acad Sci U S A. 1993 Dec 1;90(23):11257-61. PMID:8248237

1 Structural highlights
2 Function
3 Evolutionary Conservation
4 Publication Abstract from PubMed
5 See Also
6 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1xx2"

@@ Line 5: / Line 5: @@
 </td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1bls|1bls]], [[2blt|2blt]]</td></tr>
 <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><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></td></tr>
-<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1xx2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1xx2 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1xx2 RCSB], [http://www.ebi.ac.uk/pdbsum/1xx2 PDBsum]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1xx2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1xx2 OCA], [http://pdbe.org/1xx2 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1xx2 RCSB], [http://www.ebi.ac.uk/pdbsum/1xx2 PDBsum]</span></td></tr>
 </table>
 == Function ==
@@ Line 27: / Line 27: @@
 From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
 </div>
+<div class="pdbe-citations 1xx2" style="background-color:#fffaf0;"></div>
 ==See Also==

1xx2

From Proteopedia

Revision as of 14:13, 10 September 2015

Refinement of P99 beta-lactamase from Enterobacter cloacae

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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