1aqe
From Proteopedia
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| - | [[Image:1aqe.jpg|left|200px]]<br /><applet load="1aqe" size=" | + | [[Image:1aqe.jpg|left|200px]]<br /><applet load="1aqe" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1aqe, resolution 2.2Å" /> | caption="1aqe, resolution 2.2Å" /> | ||
'''CRYSTAL STRUCTURE OF THE Y73E MUTANT OF CYTOCHROME C OF CLASS III (AMBLER) 26 KD'''<br /> | '''CRYSTAL STRUCTURE OF THE Y73E MUTANT OF CYTOCHROME C OF CLASS III (AMBLER) 26 KD'''<br /> | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1AQE is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Desulfovibrio_desulfuricans Desulfovibrio desulfuricans] with SO4 and HEM as [http://en.wikipedia.org/wiki/ligands ligands]. Known structural/functional Sites: <scene name='pdbsite=HE1:Bis-Histidinyl Ligated Fe In A Protoporphyrin Ix Covalen ...'>HE1</scene>, <scene name='pdbsite=HE2:Bis-Histidinyl Ligated Fe In A Protoporphyrin Ix Covalen ...'>HE2</scene>, <scene name='pdbsite=HE3:Bis-Histidinyl Ligated Fe In A Protoporphyrin Ix Covalen ...'>HE3</scene> and <scene name='pdbsite=HE4:Bis-Histidinyl Ligated Fe In A Protoporphyrin Ix Covalen ...'>HE4</scene>. Full crystallographic information is available from [http:// | + | 1AQE is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Desulfovibrio_desulfuricans Desulfovibrio desulfuricans] with <scene name='pdbligand=SO4:'>SO4</scene> and <scene name='pdbligand=HEM:'>HEM</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Known structural/functional Sites: <scene name='pdbsite=HE1:Bis-Histidinyl+Ligated+Fe+In+A+Protoporphyrin+Ix+Covalen+...'>HE1</scene>, <scene name='pdbsite=HE2:Bis-Histidinyl+Ligated+Fe+In+A+Protoporphyrin+Ix+Covalen+...'>HE2</scene>, <scene name='pdbsite=HE3:Bis-Histidinyl+Ligated+Fe+In+A+Protoporphyrin+Ix+Covalen+...'>HE3</scene> and <scene name='pdbsite=HE4:Bis-Histidinyl+Ligated+Fe+In+A+Protoporphyrin+Ix+Covalen+...'>HE4</scene>. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1AQE OCA]. |
==Reference== | ==Reference== | ||
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[[Category: point mutant]] | [[Category: point mutant]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Feb 3 09:31:19 2008'' |
Revision as of 07:31, 3 February 2008
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CRYSTAL STRUCTURE OF THE Y73E MUTANT OF CYTOCHROME C OF CLASS III (AMBLER) 26 KD
Overview
A combination of structural, kinetic, and interaction experiments has been, used to study the role of a highly conserved aromatic residue, Tyr73, parallel to the sixth heme axial ligand of heme 4 in multiheme cytochrome, c3 (Mr = 26 000), also called cytochrome cc3 or octaheme cytochrome, from, Desulfovibrio desulfuricans Norway. This residue is expected to be, involved in intermolecular electron transfer and protein-protein, interaction, since heme 4 is described to be the interaction site between, physiological partners. The kinetic experiments show that the Y73E, replacement provokes no significant change in the electron-transfer, reaction with the physiological partner, the [NiFeSe] hydrogenase, but, that the protein-protein interaction between cytochrome c3 (Mr = 26 000), and hydrogenase is strongly affected by the mutation. The aromatic residue, does not play a role in maintaining the axial heme ligand in a particular, orientation, since the mutation did not affect the orientation of, histidine 77, the sixth axial ligand of heme 4. The structural analysis by, X-ray crystallography clearly shows that a rearrangement of the charged, residues in the vicinity of the mutation site is responsible for the, change in protein-protein interaction, which is of an electrostatic, nature. Lys22 and Arg66, residues which are located at the interacting, surface, are twisted toward the mutated position Glu73 in order to, compensate for the negative charge and therefore are no longer accessible, for the docking with a physiological partner. Tyr73 has instead a, structural function and probably a role in maintaining the hydrophobic, environment of the heme 4 cavity rather than a function in the, intermolecular electron transfer with the physiological partners.
About this Structure
1AQE is a Single protein structure of sequence from Desulfovibrio desulfuricans with and as ligands. Known structural/functional Sites: , , and . Full crystallographic information is available from OCA.
Reference
Structural and kinetic studies of the Y73E mutant of octaheme cytochrome c3 (Mr = 26 000) from Desulfovibrio desulfuricans Norway., Aubert C, Giudici-Orticoni MT, Czjzek M, Haser R, Bruschi M, Dolla A, Biochemistry. 1998 Feb 24;37(8):2120-30. PMID:9485359
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