1SQQ
Crystal Structure Analysis of Bovine Bc1 with Methoxy Acrylate Stilbene (MOAS)
Summary for 1SQQ
| Entry DOI | 10.2210/pdb1sqq/pdb |
| Related | 1L0L 1QCR 1SQB 1SQP |
| Descriptor | Ubiquinol-cytochrome-c reductase complex core protein I, mitochondrial precursor, Ubiquinol-cytochrome c reductase complex 7.2 kDa protein, Ubiquinol-cytochrome c reductase complex 6.4 kDa protein, ... (16 entities in total) |
| Functional Keywords | cytochrome bc1, qo inhibitor, membrane protein, electron transport, oxidoreductase |
| Biological source | Bos taurus (cattle) More |
| Cellular location | Mitochondrion inner membrane; Peripheral membrane protein; Matrix side: P31800 P23004 Mitochondrion inner membrane: P00130 P07552 P13272 P00129 P13271 P00126 P13272 Mitochondrion inner membrane; Multi-pass membrane protein (By similarity): P00157 Mitochondrion inner membrane; Single-pass membrane protein; Intermembrane side: P00125 |
| Total number of polymer chains | 11 |
| Total formula weight | 243937.51 |
| Authors | |
| Primary citation | Esser, L.,Quinn, B.,Li, Y.F.,Zhang, M.,Elberry, M.,Yu, L.,Yu, C.A.,Xia, D. Crystallographic studies of quinol oxidation site inhibitors: a modified classification of inhibitors for the cytochrome bc(1) complex. J.Mol.Biol., 341:281-302, 2004 Cited by PubMed Abstract: Cytochrome bc(1) is an integral membrane protein complex essential for cellular respiration and photosynthesis; it couples electron transfer from quinol to cytochrome c to proton translocation across the membrane. Specific bc(1) inhibitors have not only played crucial roles in elucidating the mechanism of bc(1) function but have also provided leads for the development of novel antibiotics. Crystal structures of bovine bc(1) in complex with the specific Q(o) site inhibitors azoxystrobin, MOAS, myxothiazol, stigmatellin and 5-undecyl-6-hydroxy-4,7-dioxobenzothiazole were determined. Interactions, conformational changes and possible mechanisms of resistance, specific to each inhibitor, were defined. Residues and secondary structure elements that are capable of discriminating different classes of Q(o) site inhibitors were identified for the cytochrome b subunit. Directions in the displacement of the cd1 helix of cytochrome b subunit in response to various Q(o) site inhibitors were correlated to the binary conformational switch of the extrinsic domain of the iron-sulfur protein subunit. The new structural information, together with structures previously determined, provide a basis that, combined with biophysical and mutational data, suggest a modification to the existing classification of bc(1) inhibitors. bc(1) inhibitors are grouped into three classes: class P inhibitors bind to the Q(o) site, class N inhibitors bind to the Q(i) site and the class PN inhibitors target both sites. Class P contains two subgroups, Pm and Pf, that are distinct by their ability to induce mobile or fixed conformation of iron-sulfur protein. PubMed: 15312779DOI: 10.1016/j.jmb.2004.05.065 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (3 Å) |
Structure validation
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