TY - JOUR
T1 - Atomic Resolution Structures of Rieske Iron-Sulfur Protein
T2 - Role of Hydrogen Bonds in Tuning the Redox Potential of Iron-Sulfur Clusters
AU - Kolling, Derrick J.
AU - Brunzelle, Joseph S.
AU - Lhee, Sang Moon
AU - Crofts, Antony R.
AU - Nair, Satish K.
N1 - Funding Information:
We thank Drs. Lisa Keefe and Irina Koshelev for support at Beamline 17-ID (IMCA-CAT), Drs. Marie Graham and Zhongmin Jin for support at Beamline 22-ID (SER-CAT), and Dr. Zdzislaw Wawrzak for support at Beamline 5-ID (DND-CAT); all researchers are at Argonne National Labs. We thank Denise Lorenz, Conor Danstrom, and Nathan Wetter for initial crystallization efforts. A.R.C. thanks Judy Hirst for advice in setting up the protein film voltammetry apparatus. S.K.N. thanks Dr. Colin Wraight for his continued support of structural biology at the University of Illinois at Urbana-Champaign (UIUC). This work was supported by grants from the American Cancer Society and UIUC (S.K.N.) and the National Institutes of Health GM35438 (A.R.C.). S.K.N. and A.R.C. designed research. D.J.K., SM.L., J.S.B., and S.K.N. performed research. D.J.K., SM.L., A.R.C., and S.K.N. analyzed data. S.K.N. wrote the paper with input from D.J.K. and A.R.C. The authors declare no competing interests.
PY - 2007/1
Y1 - 2007/1
N2 - The Rieske [2Fe-2S] iron-sulfur protein of cytochrome bc1 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 Å 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 Å and 1.1 Å. 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.
AB - The Rieske [2Fe-2S] iron-sulfur protein of cytochrome bc1 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 Å 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 Å and 1.1 Å. 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.
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U2 - 10.1016/j.str.2006.11.012
DO - 10.1016/j.str.2006.11.012
M3 - Article
C2 - 17223530
AN - SCOPUS:33846263979
SN - 0969-2126
VL - 15
SP - 29
EP - 38
JO - Structure with Folding & design
JF - Structure with Folding & design
IS - 1
ER -