1hzo: Difference between revisions
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
[[Image:1hzo.jpg|left|200px]] | [[Image:1hzo.jpg|left|200px]] | ||
<!-- | |||
The line below this paragraph, containing "STRUCTURE_1hzo", creates the "Structure Box" on the page. | |||
You may change the PDB parameter (which sets the PDB file loaded into the applet) | |||
or the SCENE parameter (which sets the initial scene displayed when the page is loaded), | |||
or leave the SCENE parameter empty for the default display. | |||
| | --> | ||
| | {{STRUCTURE_1hzo| PDB=1hzo | SCENE= }} | ||
}} | |||
'''STRUCTURE OF CLASS A CEPHALOSPORINASE FROM PROTEUS VULGARIS K1''' | '''STRUCTURE OF CLASS A CEPHALOSPORINASE FROM PROTEUS VULGARIS K1''' | ||
| Line 31: | Line 28: | ||
[[Category: Mayama, K.]] | [[Category: Mayama, K.]] | ||
[[Category: Nukaga, M.]] | [[Category: Nukaga, M.]] | ||
[[Category: | [[Category: Cephalosporinase]] | ||
[[Category: | [[Category: Class a beta-lactamase]] | ||
[[Category: | [[Category: Hydrolase]] | ||
[[Category: | [[Category: Mixed alpha/beta]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 19:24:14 2008'' | |||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | |||
Revision as of 16:24, 2 May 2008
STRUCTURE OF CLASS A CEPHALOSPORINASE FROM PROTEUS VULGARIS K1
Overview
The structure of a chromosomal extended-spectrum beta-lactamase (ESBL) having the ability to hydrolyze cephalosporins including cefuroxime and ceftazidime has been determined by X-ray crystallography to 1.75 A resolution. The species-specific class A beta-lactamase from Proteus vulgaris K1 was crystallized at pH 6.25 and its structure solved by molecular replacement. Refinement of the model resulted in crystallographic R and R(free) of 16.9 % and 19.3 %, respectively. The folding of the K1 enzyme is broadly similar to that of non-ESBL TEM-type beta-lactamases (2 A rmsd for C(alpha)) and differs by only 0.35 A for all atoms of six conserved residues in the catalytic site. Other residues promoting extended-spectrum activity in K1 include the side-chains of atypical residues Ser237 and Lys276. These side-chains are linked by two water molecules, one of which lies in the position normally filled by the guanidinium group of Arg244, present in most non-ESBL enzymes but absent from K1. The ammonium group of Lys276, ca 3.5 A from the virtual Arg244 guanidinium position, may interact with polar R2 substitutents on the dihydrothiazene ring of cephalosporins.
About this Structure
1HZO is a Single protein structure of sequence from Proteus vulgaris. Full crystallographic information is available from OCA.
Reference
Structure of an extended-spectrum class A beta-lactamase from Proteus vulgaris K1., Nukaga M, Mayama K, Crichlow GV, Knox JR, J Mol Biol. 2002 Mar 15;317(1):109-17. PMID:11916382 Page seeded by OCA on Fri May 2 19:24:14 2008
