1e67: Difference between revisions

Revision as of 14:42, 2 May 2008

ZN-AZURIN FROM PSEUDOMONAS AERUGINOSA

OverviewOverview

Azurin*, a by-product of heterologous expression of the gene encoding the blue copper protein azurin from Pseudomonas aeruginosa in Escherichia coli, was characterized by chemical analysis and electrospray ionization mass spectrometry, and its structure determined by X-ray crystallography. It was shown that azurin* is native azurin with its copper atom replaced by zinc in the metal binding site. Zinc is probably incorporated in the apo-protein after its expression and transport into the periplasm. Holo-azurin can be reconstituted from azurin* by prolonged exposure of the protein to high copper ion concentrations or unfolding of the protein and refolding in the presence of copper ions. An X-ray crystallographic analysis of azurin* at 0.21-nm resolution revealed that the overall structure of azurin is not perturbed by the metal exchange. However, the geometry of the co-ordination sphere changes from trigonal bipyramidal in the case of copper azurin to distorted tetrahedral for the zinc protein. The copper ligand Met121 is no longer co-ordinated to zinc which adopts a position close to the carbonyl oxygen atom from residue Gly45. The polypeptide structure surrounding the metal site undergoes moderate reorganization upon zinc binding. The largest displacement observed is for the carbonyl oxygen from residue Gly45, which is involved in copper and zinc binding. It moves by 0.03 nm towards the zinc, thereby reducing its distance to the metal from 0.29 nm in the copper protein to 0.23 nm in the derivative.

About this StructureAbout this Structure

1E67 is a Single protein structure of sequence from Pseudomonas aeruginosa. Full crystallographic information is available from OCA.

ReferenceReference

Characterization and crystal structure of zinc azurin, a by-product of heterologous expression in Escherichia coli of Pseudomonas aeruginosa copper azurin., Nar H, Huber R, Messerschmidt A, Filippou AC, Barth M, Jaquinod M, van de Kamp M, Canters GW, Eur J Biochem. 1992 May 1;205(3):1123-9. PMID:1576995 Page seeded by OCA on Fri May 2 14:42:55 2008

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OCA

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 [[Image:1e67.gif|left|200px]]
- {{Structure
+<!--
-|PDB= 1e67 |SIZE=350|CAPTION= <scene name='initialview01'>1e67</scene>, resolution 2.14&Aring;
+The line below this paragraph, containing "STRUCTURE_1e67", creates the "Structure Box" on the page.
-|SITE= <scene name='pdbsite=AC1:Zn+Binding+Site+For+Chain+A'>AC1</scene>, <scene name='pdbsite=AC2:Zn+Binding+Site+For+Chain+B'>AC2</scene>, <scene name='pdbsite=AC3:Zn+Binding+Site+For+Chain+C'>AC3</scene>, <scene name='pdbsite=AC4:Zn+Binding+Site+For+Chain+D'>AC4</scene> and <scene name='pdbsite=AC5:No3+Binding+Site+For+Chain+A'>AC5</scene>
+You may change the PDB parameter (which sets the PDB file loaded into the applet)
-|LIGAND= <scene name='pdbligand=NO3:NITRATE+ION'>NO3</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene>
+or the SCENE parameter (which sets the initial scene displayed when the page is loaded),
-|ACTIVITY=
+or leave the SCENE parameter empty for the default display.
-|GENE=
+-->
-|DOMAIN=
+{{STRUCTURE_1e67|  PDB=1e67  |  SCENE=  }}
-|RELATEDENTRY=
-|RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1e67 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1e67 OCA], [http://www.ebi.ac.uk/pdbsum/1e67 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1e67 RCSB]</span>
-}}
 '''ZN-AZURIN FROM PSEUDOMONAS AERUGINOSA'''
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 [[Category: Messerschmidt, A.]]
 [[Category: Nar, H.]]
-[[Category: electron transport(copper binding)]]
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May  2 14:42:55 2008''
-''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 19:55:58 2008''