1jzj: Difference between revisions
No edit summary |
No edit summary |
||
Line 1: | Line 1: | ||
[[Image:1jzj.gif|left|200px]] | [[Image:1jzj.gif|left|200px]] | ||
<!-- | |||
The line below this paragraph, containing "STRUCTURE_1jzj", 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_1jzj| PDB=1jzj | SCENE= }} | |||
}} | |||
'''Pseudomonas aeruginosa Azurin Os(bpy)2(im)(His83)''' | '''Pseudomonas aeruginosa Azurin Os(bpy)2(im)(His83)''' | ||
Line 29: | Line 26: | ||
[[Category: Gray, H B.]] | [[Category: Gray, H B.]] | ||
[[Category: Winkler, J R.]] | [[Category: Winkler, J R.]] | ||
[[Category: | [[Category: Blue-copper]] | ||
[[Category: | [[Category: Electron transfer]] | ||
[[Category: | [[Category: Osmium]] | ||
[[Category: | [[Category: Tunneling]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 22:06:48 2008'' | |||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on |
Revision as of 22:06, 2 May 2008
Pseudomonas aeruginosa Azurin Os(bpy)2(im)(His83)
OverviewOverview
Rates of reduction of Os(III), Ru(III), and Re(I) by Cu(I) in His83-modified Pseudomonas aeruginosa azurins (M-Cu distance approximately 17 A) have been measured in single crystals, where protein conformation and surface solvation are precisely defined by high-resolution X-ray structure determinations: 1.7(8) x 10(6) s(-1) (298 K), 1.8(8) x 10(6) s(-1) (140 K), [Ru(bpy)2(im)(3+)-]; 3.0(15) x 10(6) s(-1) (298 K), [Ru(tpy)(bpy)(3+)-]; 3.0(15) x 10(6) s(-1) (298 K), [Ru(tpy)(phen)(3+)-]; 9.0(50) x 10(2) s(-1) (298 K), [Os(bpy)2(im)(3+)-]; 4.4(20) x 10(6) s(-1) (298 K), [Re(CO)3(phen)(+)] (bpy = 2,2'-bipyridine; im = imidazole; tpy = 2,2':6',2' '-terpyridine; phen = 1,10-phenanthroline). The time constants for electron tunneling in crystals are roughly the same as those measured in solution, indicating very similar protein structures in the two states. High-resolution structures of the oxidized (1.5 A) and reduced (1.4 A) states of Ru(II)(tpy)(phen)(His83)Az establish that very small changes in copper coordination accompany reduction but reveal a shorter axial interaction between copper and the Gly45 peptide carbonyl oxygen [2.6 A for Cu(II)] than had been recognized previously. Although Ru(bpy)2(im)(His83)Az is less solvated in the crystal, the reorganization energy for Cu(I) --> Ru(III) electron transfer falls in the range (0.6-0.8 eV) determined experimentally for the reaction in solution. Our work suggests that outer-sphere protein reorganization is the dominant activation component required for electron tunneling.
About this StructureAbout this Structure
1JZJ is a Single protein structure of sequence from Pseudomonas aeruginosa. Full crystallographic information is available from OCA.
ReferenceReference
Electron tunneling in single crystals of Pseudomonas aeruginosa azurins., Crane BR, Di Bilio AJ, Winkler JR, Gray HB, J Am Chem Soc. 2001 Nov 28;123(47):11623-31. PMID:11716717 Page seeded by OCA on Fri May 2 22:06:48 2008