1i1o
From Proteopedia
| Line 1: | Line 1: | ||
[[Image:1i1o.gif|left|200px]] | [[Image:1i1o.gif|left|200px]] | ||
| - | + | <!-- | |
| - | + | The line below this paragraph, containing "STRUCTURE_1i1o", 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_1i1o| PDB=1i1o | SCENE= }} | |
| - | + | ||
| - | + | ||
| - | }} | + | |
'''ROOM TEMPERATURE CRYSTAL STRUCTURE FLAVODOXIN D. VULGARIS MUTANT Y98H AT 2.0 ANG. RESOLUTION''' | '''ROOM TEMPERATURE CRYSTAL STRUCTURE FLAVODOXIN D. VULGARIS MUTANT Y98H AT 2.0 ANG. RESOLUTION''' | ||
| Line 28: | Line 25: | ||
[[Category: Watenpaugh, K D.]] | [[Category: Watenpaugh, K D.]] | ||
[[Category: Watt, W.]] | [[Category: Watt, W.]] | ||
| - | [[Category: | + | [[Category: Electron transfer]] |
| - | [[Category: | + | [[Category: High resolution]] |
| - | [[Category: | + | [[Category: Redox potential]] |
| - | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 19:28:16 2008'' | |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | |
Revision as of 16:28, 2 May 2008
ROOM TEMPERATURE CRYSTAL STRUCTURE FLAVODOXIN D. VULGARIS MUTANT Y98H AT 2.0 ANG. RESOLUTION
Overview
The structures for two mutants at the Tyr98 site of Desulfovibrio vulgaris flavodoxin have been determined. The first, a tyrosine-to-histidine (Y98H) variant, was determined at the moderately high resolution of 2.0 A, while the tyrosine-to-tryptophan variant (Y98W) yielded very high resolution data (beyond 1.5 A) allowing a detailed look at the water structure, alternate side-chain conformations and the planarity of the FMN. Both structures were solved by molecular replacement beginning with the native (P2A) coordinates as a starting point. The Y98H variant of D. vulgaris flavodoxin crystallizes in space group P2(1)2(1)2(1), with unit-cell parameters a = 41.96, b = 61.45, c = 57.04 A, while the Y98W mutant adopts space group P2(1), with a = 41.29, b = 55.82, c = 32.52 A, beta = 100.68 degrees. Refinement for both mutants utilized PROLSQ followed by, for the high-resolution Y98W structure, anisotropic refinement as implemented in SHELXL. Final R factors of 17% for the Y98H mutant and 9.8% for the Y98W mutant were obtained. For the high-resolution (1.5 A) Y98W mutant, 31,010 unique reflections were collected from a single crystal. The final model includes 273 solvent molecules, with eight side chains assuming multiple conformations. At this resolution, the detailed conformation of the FMN can be observed, with both a bow and twist being noted. A comparison is made between the two mutants and the different oxidation states of the native flavodoxin. Although both mutants show similar E(2) (oxidized/semiquinone) one-electron redox potentials to the native, the E(1) (semiquinone/hydroquinone) redox potential for the Y98H mutant is significantly different from that of the Y98W variant and the native protein. The surprising similarity in the folding of the polypeptide chain 60--64 between the two mutants and the reduced states of the native is discussed. The interaction between O61 and N5 in the flavin is discussed because of the new conformation of this loop.
About this Structure
1I1O is a Single protein structure of sequence from Desulfovibrio vulgaris. Full crystallographic information is available from OCA.
Reference
Structures and comparison of the Y98H (2.0 A) and Y98W (1.5 A) mutants of flavodoxin (Desulfovibrio vulgaris)., Reynolds RA, Watt W, Watenpaugh KD, Acta Crystallogr D Biol Crystallogr. 2001 Apr;57(Pt 4):527-35. PMID:11264581 Page seeded by OCA on Fri May 2 19:28:16 2008
