1nyk
From Proteopedia
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Crystal Structure of the Rieske protein from Thermus thermophilus
Overview
The structure of the soluble Rieske protein from Thermus thermophilus has, been determined at a resolution of 1.3 A at pH 8.5 using multiwavelength, anomalous dispersion (MAD) techniques. This is the first report of a, Rieske protein from a menaquinone-utilizing organism. The structure shows, an overall fold similar to previously reported Rieske proteins. A novel, feature of this crystal form appears to be a shared hydrogen between the, His-134 imidazole ring ligated to Fe2 of the [2Fe-2S] cluster and its, symmetry partner, His-134', one being formally an imidazolate anion, Fe2-(His-134)N(epsilon)(-)...H-N(epsilon')(His-134')-Fe2', in which, crystallographic C(2) axes pass equidistant between, N(epsilon)...N(epsilon') and normal to the line defined by, N(epsilon)...N(epsilon'). This provides evidence for a stable, oxidized, cluster with a His(-) ligand and lends support to a previously proposed, mechanism of coupled proton and electron transfer. A detailed comparison, of the Thermus Rieske protein with six other Rieske and Rieske-type, proteins indicates: (a) The cluster binding domain is tightly conserved., (b) The 3-D structure of the 10 beta-strand fold is conserved, even among, the most divergent proteins. (c) There is an approximately linear relation, between acid-pH redox potential and number of H-bonds to the cluster. (d), These proteins have two faces, one points into the larger complex (bc(1), b(6)f, or other), is involved in the proton coupled electron transfer, function, and is highly conserved. The second is oriented toward the, solvent and shows wide variation in charge, sequence, length, hydrophobicity, and secondary elements in the loops that connect the, beta-sheets.
About this Structure
1NYK is a Single protein structure of sequence from Thermus thermophilus with MG and FES as ligands. Full crystallographic information is available from OCA.
Reference
High-resolution structure of the soluble, respiratory-type Rieske protein from Thermus thermophilus: analysis and comparison., Hunsicker-Wang LM, Heine A, Chen Y, Luna EP, Todaro T, Zhang YM, Williams PA, McRee DE, Hirst J, Stout CD, Fee JA, Biochemistry. 2003 Jun 24;42(24):7303-17. PMID:12809486
Page seeded by OCA on Sun Nov 25 00:03:53 2007
