1jzh
From Proteopedia
(New page: 200px<br /><applet load="1jzh" size="450" color="white" frame="true" align="right" spinBox="true" caption="1jzh, resolution 1.70Å" /> '''Pseudomonas aerugino...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:1jzh.gif|left|200px]]<br /><applet load="1jzh" size=" | + | [[Image:1jzh.gif|left|200px]]<br /><applet load="1jzh" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1jzh, resolution 1.70Å" /> | caption="1jzh, resolution 1.70Å" /> | ||
'''Pseudomonas aeruginosa Azurin Ru(tpy)(bpy)(His83)'''<br /> | '''Pseudomonas aeruginosa Azurin Ru(tpy)(bpy)(His83)'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Rates of reduction of Os(III), Ru(III), and Re(I) by Cu(I) in | + | 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 Structure== | ==About this Structure== | ||
| - | 1JZH is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Pseudomonas_aeruginosa Pseudomonas aeruginosa] with CU and RTA as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 1JZH is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Pseudomonas_aeruginosa Pseudomonas aeruginosa] with <scene name='pdbligand=CU:'>CU</scene> and <scene name='pdbligand=RTA:'>RTA</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1JZH OCA]. |
==Reference== | ==Reference== | ||
| Line 13: | Line 13: | ||
[[Category: Pseudomonas aeruginosa]] | [[Category: Pseudomonas aeruginosa]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Bilio, A | + | [[Category: Bilio, A J.Di.]] |
| - | [[Category: Crane, B | + | [[Category: Crane, B R.]] |
| - | [[Category: Winkler, J | + | [[Category: Winkler, J R.]] |
[[Category: CU]] | [[Category: CU]] | ||
[[Category: RTA]] | [[Category: RTA]] | ||
| Line 23: | Line 23: | ||
[[Category: tunneling]] | [[Category: tunneling]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:28:26 2008'' |
Revision as of 11:28, 21 February 2008
|
Pseudomonas aeruginosa Azurin Ru(tpy)(bpy)(His83)
Overview
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 Structure
1JZH is a Single protein structure of sequence from Pseudomonas aeruginosa with and as ligands. Full crystallographic information is available from OCA.
Reference
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 Thu Feb 21 13:28:26 2008
