1qlb: Difference between revisions
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==Overview== | ==Overview== | ||
Fumarate reductase couples the reduction of fumarate to succinate to the, oxidation of quinol to quinone, in a reaction opposite to that catalysed, by the related complex II of the respiratory chain (succinate, dehydrogenase). Here we describe the crystal structure at 2.2 A resolution, of the three protein subunits containing fumarate reductase from the, anaerobic bacterium Wolinella succinogenes. Subunit A contains the site of, fumarate reduction and a covalently bound flavin adenine dinucleotide, prosthetic group. Subunit B contains three iron-sulphur centres. The, menaquinol-oxidizing subunit C consists of five membrane-spanning, primarily helical segments and binds two haem b molecules. On the basis of, the structure, we propose a pathway of electron transfer from the dihaem, . | Fumarate reductase couples the reduction of fumarate to succinate to the, oxidation of quinol to quinone, in a reaction opposite to that catalysed, by the related complex II of the respiratory chain (succinate, dehydrogenase). Here we describe the crystal structure at 2.2 A resolution, of the three protein subunits containing fumarate reductase from the, anaerobic bacterium Wolinella succinogenes. Subunit A contains the site of, fumarate reduction and a covalently bound flavin adenine dinucleotide, prosthetic group. Subunit B contains three iron-sulphur centres. The, menaquinol-oxidizing subunit C consists of five membrane-spanning, primarily helical segments and binds two haem b molecules. On the basis of, the structure, we propose a pathway of electron transfer from the dihaem, cytochrome b to the site of fumarate reduction and a mechanism of fumarate, reduction. The relative orientations of the soluble and membrane-embedded, subunits of succinate:quinone oxidoreductases appear to be unique. | ||
==About this Structure== | ==About this Structure== | ||
1QLB is a | 1QLB is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Wolinella_succinogenes Wolinella succinogenes] with CA, HEM, FES, F3S, SF4, FAD, FMR and LMT as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Succinate_dehydrogenase Succinate dehydrogenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.3.99.1 1.3.99.1] Structure known Active Sites: FA1, FA2, FS1, FS2, FS3, FS4, FS5, FS6, HE1 and HE2. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1QLB OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: succinate dehydrogenase]] | [[Category: succinate dehydrogenase]] | ||
''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Mon Nov 5 14:39:29 2007'' | ||
