This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.


Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.


1gce

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Line 1: Line 1:
-
[[Image:1gce.jpg|left|200px]]
+
{{Seed}}
 +
[[Image:1gce.png|left|200px]]
<!--
<!--
Line 9: Line 10:
{{STRUCTURE_1gce| PDB=1gce | SCENE= }}
{{STRUCTURE_1gce| PDB=1gce | SCENE= }}
-
'''STRUCTURE OF THE BETA-LACTAMASE OF ENTEROBACTER CLOACAE GC1'''
+
===STRUCTURE OF THE BETA-LACTAMASE OF ENTEROBACTER CLOACAE GC1===
-
==Overview==
+
<!--
-
A class C beta-lactamase from a clinical isolate of Enterobacter cloacae strain GC1 with improved hydrolytic activity for oxyimino beta-lactam antibiotics has been analyzed by X-ray crystallography to 1.8 A resolution. Relative to the wild-type P99 beta-lactamase, this natural mutant contains a highly unique tandem repeat Ala211-Val212-Arg213 [Nugaka et al. (1995) J. Biol. Chem. 270, 5729-5735]. The 39.4 kDa chromosomal beta-lactamase crystallizes from poly(ethylene glycol) 8000 in potassium phosphate in space group P2(1)2(1)2 with cell dimensions a = 78.0 A, b = 69.5 A, and c = 63.1 A. The crystal structure was solved by the molecular replacement method, and the model has been refined to an R-factor of 0.20 for all nonzero data from 8 to 1.8 A. Deviations of model bonds and angles from ideal values are 0.008 A and 1.4 degrees, respectively. Overlay of alpha-carbon atoms in the GC1 and P99 beta-lactamases results in an rms deviation of 0.6 A. Largest deviations occur in a loop containing Gln120 and in the Omega loop region (200-218) where the three residues 213-215 are disordered. Possibly as a result of this disorder, the width of the opening to the substrate binding cavity, as measured from the 318-324 beta-strand to two loops containing Gln120 and Tyr150 on the other side, is 0.6-1.4 A wider than in P99. It is suggested that conformational flexibility in the expanded Omega loop, and its influence on adjacent protein structure, may facilitate hydrolysis of oxyimino beta-lactams by making the acyl intermediate more open to attack by water. Nevertheless, backbone atoms in core catalytic site residues Ser64, Lys67, Tyr150, Asn152, Lys318, and Ser321 deviate only 0.4 A (rmsd) from atoms in P99. A rotation of a potential catalytic base, Tyr150, relative to P99 at pH 8, is consistent with the requirement for a lower than normal pK(a) for this residue.
+
The line below this paragraph, {{ABSTRACT_PUBMED_10441119}}, adds the Publication Abstract to the page
 +
(as it appears on PubMed at http://www.pubmed.gov), where 10441119 is the PubMed ID number.
 +
-->
 +
{{ABSTRACT_PUBMED_10441119}}
==About this Structure==
==About this Structure==
Line 32: Line 36:
[[Category: Drug design]]
[[Category: Drug design]]
[[Category: Extended-spectrum beta- lactamase]]
[[Category: Extended-spectrum beta- lactamase]]
-
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 17:24:38 2008''
+
 
 +
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Tue Jul 1 05:04:35 2008''

Revision as of 02:04, 1 July 2008

Template:STRUCTURE 1gce

STRUCTURE OF THE BETA-LACTAMASE OF ENTEROBACTER CLOACAE GC1

Template:ABSTRACT PUBMED 10441119

About this Structure

1GCE is a Single protein structure of sequence from Enterobacter cloacae. Full crystallographic information is available from OCA.

Reference

Structure of the extended-spectrum class C beta-lactamase of Enterobacter cloacae GC1, a natural mutant with a tandem tripeptide insertion., Crichlow GV, Kuzin AP, Nukaga M, Mayama K, Sawai T, Knox JR, Biochemistry. 1999 Aug 10;38(32):10256-61. PMID:10441119

Page seeded by OCA on Tue Jul 1 05:04:35 2008

Proteopedia Page Contributors and Editors (what is this?)

OCA

Personal tools