2num
Soluble domain of Rieske Iron-Sulfur Protein
OverviewOverview
The Rieske [2Fe-2S] iron-sulfur protein of cytochrome bc(1) functions as the initial electron acceptor in the rate-limiting step of the catalytic reaction. Prior studies have established roles for a number of conserved residues that hydrogen bond to ligands of the [2Fe-2S] cluster. We have constructed site-specific variants at two of these residues, measured their thermodynamic and functional properties, and determined atomic resolution X-ray crystal structures for the native protein at 1.2 A resolution and for five variants (Ser-154-->Ala, Ser-154-->Thr, Ser-154-->Cys, Tyr-156-->Phe, and Tyr-156-->Trp) to resolutions between 1.5 A and 1.1 A. These structures and complementary biophysical data provide a molecular framework for understanding the role hydrogen bonds to the cluster play in tuning thermodynamic properties, and hence the rate of this bioenergetic reaction. These studies provide a detailed structure-function dissection of the role of hydrogen bonds in tuning the redox potentials of [2Fe-2S] clusters.
About this StructureAbout this Structure
2NUM is a Single protein structure of sequence from Rhodobacter sphaeroides. Full crystallographic information is available from OCA.
ReferenceReference
Atomic resolution structures of rieske iron-sulfur protein: role of hydrogen bonds in tuning the redox potential of iron-sulfur clusters., Kolling DJ, Brunzelle JS, Lhee S, Crofts AR, Nair SK, Structure. 2007 Jan;15(1):29-38. PMID:17223530 Page seeded by OCA on Sun May 4 09:55:53 2008