2h89

Avian Respiratory Complex II with Malonate Bound

spinqualitylabelsall models 2h89, resolution 2.40Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 2h89 is a 4 chain structure with sequence from Gallus gallus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 2.4Å Ligands: BHG, FAD, FES, HEM, K, MLI, PEE Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function SDHA_CHICK Flavoprotein (FP) subunit of succinate dehydrogenase (SDH) that is involved in complex II of the mitochondrial electron transport chain and is responsible for transferring electrons from succinate to ubiquinone (coenzyme Q). Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed Mitochondrial Complex II (succinate:ubiquinone oxidoreductase) is purified in a partially inactivated state, which can be activated by removal of tightly bound oxaloacetate (E.B. Kearney, et al., Biochem. Biophys. Res. Commun. 49 1115-1121). We crystallized Complex II in the presence of oxaloacetate or with the endogenous inhibitor bound. The structure showed a ligand essentially identical to the "malate-like intermediate" found in Shewanella Flavocytochrome c crystallized with fumarate (P. Taylor, et al., Nat. Struct. Biol. 6 1108-1112) Crystallization of Complex II in the presence of excess fumarate also gave the malate-like intermediate or a mixture of that and fumarate at the active site. In order to more conveniently monitor the occupation state of the dicarboxylate site, we are developing a library of UV/Vis spectral effects induced by binding different ligands to the site. Treatment with fumarate results in rapid development of the fumarate difference spectrum and then a very slow conversion into a species spectrally similar to the OAA-liganded complex. Complex II is known to be capable of oxidizing malate to the enol form of oxaloacetate (Y.O. Belikova, et al., Biochim. Biophys. Acta 936 1-9). The observations above suggest it may also be capable of interconverting fumarate and malate. It may be useful for understanding the mechanism and regulation of the enzyme to identify the malate-like intermediate and its pathway of formation from oxaloacetate or fumarate. Crystallographic studies of the binding of ligands to the dicarboxylate site of Complex II, and the identity of the ligand in the "oxaloacetate-inhibited" state.,Huang LS, Shen JT, Wang AC, Berry EA Biochim Biophys Acta. 2006 Sep-Oct;1757(9-10):1073-83. Epub 2006 Jul 12. PMID:16935256 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Succinate dehydrogenase 3D structures

Proteopedia Page Contributors and Editors (what is this?)

OCA