1krc
From Proteopedia
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|PDB= 1krc |SIZE=350|CAPTION= <scene name='initialview01'>1krc</scene>, resolution 2.5Å | |PDB= 1krc |SIZE=350|CAPTION= <scene name='initialview01'>1krc</scene>, resolution 2.5Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand= | + | |LIGAND= <scene name='pdbligand=CO2:CARBON+DIOXIDE'>CO2</scene>, <scene name='pdbligand=NI:NICKEL+(II)+ION'>NI</scene> |
| - | |ACTIVITY= [http://en.wikipedia.org/wiki/Urease Urease], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.5.1.5 3.5.1.5] | + | |ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/Urease Urease], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.5.1.5 3.5.1.5] </span> |
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY= | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1krc FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1krc OCA], [http://www.ebi.ac.uk/pdbsum/1krc PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1krc RCSB]</span> | ||
}} | }} | ||
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[[Category: Jabri, E.]] | [[Category: Jabri, E.]] | ||
[[Category: Karplus, P A.]] | [[Category: Karplus, P A.]] | ||
| - | [[Category: CO2]] | ||
| - | [[Category: NI]] | ||
[[Category: active site mutant]] | [[Category: active site mutant]] | ||
[[Category: nickel metalloenzyme]] | [[Category: nickel metalloenzyme]] | ||
| - | ''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 21:52:32 2008'' |
Revision as of 18:52, 30 March 2008
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| , resolution 2.5Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , | ||||||
| Activity: | Urease, with EC number 3.5.1.5 | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
CRYSTAL STRUCTURE OF KLEBSIELLA AEROGENES UREASE, ITS APOENZYME AND TWO ACTIVE SITE MUTANTS
Overview
Urease from Klebsiella aerogenes [Jabri et al. (1995) Science 268, 998-1004] is an (alpha beta gamma)3 trimer with each alpha-subunit having an (alpha beta)8-barrel domain containing a binickel active center. Here we examine structure-function relations for urease in more detail through structural analysis of the urease apoenzyme at 2.3 A resolution and mutants of two key catalytic residues (H219A and H320A) at 2.5 A resolution. With the exception of the active site, in which a water molecule takes the place of the missing carbamate and nickel atoms, the structure of the apoenzyme is nearly identical to that of the holoenzyme, suggesting a high degree of preorganization which helps explain the tight binding of nickel. In the structure of H219A, the major change involves a conformational shift and ordering of the active site flap, but a small shift in the side chain of Asp alpha 221 could contribute to the lower activity of H219A. In the H320A structure, the catalytic water, primarily a Ni-2 ligand in the holoenzyme, shifts into a bridging position. This shift shows that the nickel ligation is rather sensitive to the environment and the change in ligation may contribute to the 10(5)-fold lower activity of H320A. In addition, these results show that urease is resilient to the loss of nickel ions and mutations. Analysis of the urease tertiary/quaternary structure suggests that the stability of this enzyme may be largely due to its burial of an unusually large fraction of its residues: 50% in the gamma-subunit, 30% in the beta-subunit, and 60% in the alpha-subunit.
About this Structure
1KRC is a Protein complex structure of sequences from Klebsiella aerogenes. Full crystallographic information is available from OCA.
Reference
Structures of the Klebsiella aerogenes urease apoenzyme and two active-site mutants., Jabri E, Karplus PA, Biochemistry. 1996 Aug 20;35(33):10616-26. PMID:8718850
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