2ux7: Difference between revisions
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
[[Image:2ux7.gif|left|200px]] | [[Image:2ux7.gif|left|200px]] | ||
<!-- | |||
The line below this paragraph, containing "STRUCTURE_2ux7", 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_2ux7| PDB=2ux7 | SCENE= }} | ||
| | |||
}} | |||
'''PSEUDOAZURIN WITH ENGINEERED AMICYANIN LIGAND LOOP, REDUCED FORM, PH 7.5''' | '''PSEUDOAZURIN WITH ENGINEERED AMICYANIN LIGAND LOOP, REDUCED FORM, PH 7.5''' | ||
| Line 30: | Line 27: | ||
[[Category: Velarde, M.]] | [[Category: Velarde, M.]] | ||
[[Category: Yanagisawa, S.]] | [[Category: Yanagisawa, S.]] | ||
[[Category: | [[Category: Copper]] | ||
[[Category: | [[Category: Cupredoxin]] | ||
[[Category: | [[Category: Electron transfer]] | ||
[[Category: | [[Category: Electron transport]] | ||
[[Category: | [[Category: Loop shortening]] | ||
[[Category: | [[Category: Metal-binding]] | ||
[[Category: | [[Category: Periplasmic]] | ||
[[Category: | [[Category: Protein scaffold]] | ||
[[Category: | [[Category: Redox potential]] | ||
[[Category: | [[Category: Spectroscopic property]] | ||
[[Category: | [[Category: Transport]] | ||
[[Category: | [[Category: Type-1 copper]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun May 4 17:43:29 2008'' | |||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | |||
Revision as of 17:43, 4 May 2008
PSEUDOAZURIN WITH ENGINEERED AMICYANIN LIGAND LOOP, REDUCED FORM, PH 7.5
OverviewOverview
Atomic resolution structures of the pseudoazurin (PAZ) variant into which the shorter ligand-containing loop of amicyanin (AMI) is introduced have been determined. The mutated loop adopts a different conformation in PAZAMI than in AMI. The copper site structure is affected, with the major influence being an increased axial interaction resulting in the shortest Cu(II)-S(Met) bond observed for the cupredoxin family of electron-transfer proteins. This is accompanied by a lengthening of the important Cu-S(Cys) bond and enhanced tetragonal distortion, consistent with the influence of the PAZAMI loop contraction on the UV/vis spectrum. The change in active site geometry is the major cause of the 50 mV decrease in reduction potential. The copper site structure changes very little upon reduction, consistent with the distorted site still possessing the properties required to facilitate rapid electron transfer. The exposed His ligand on the loop protonates in the reduced protein and reasons for the increased pKa compared to that of PAZ are discussed. The area surrounding the His ligand is more hydrophobic in PAZAMI than in PAZ, while electron self-exchange, which involves homodimer formation via this surface patch, is decreased. The nature of the side chains in this region, as dictated by the sequence of the ligand-containing loop, is a more significant factor than hydrophobicity for facilitating transient protein interactions in PAZ. The structure of PAZAMI demonstrates the importance of loop-scaffold interactions for metal sites in proteins.
About this StructureAbout this Structure
2UX7 is a Single protein structure of sequence from Achromobacter cycloclastes. Full crystallographic information is available from OCA.
ReferenceReference
Influence of loop shortening on the metal binding site of cupredoxin pseudoazurin., Velarde M, Huber R, Yanagisawa S, Dennison C, Messerschmidt A, Biochemistry. 2007 Sep 4;46(35):9981-91. Epub 2007 Aug 9. PMID:17685636 Page seeded by OCA on Sun May 4 17:43:29 2008