1ci3
From Proteopedia
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CYTOCHROME F FROM THE B6F COMPLEX OF PHORMIDIUM LAMINOSUM
Overview
Cytochrome f from the photosynthetic cytochrome b(6)f complex is unique, among c-type cytochromes in its fold and heme ligation. The 1. 9-A crystal, structure of the functional, extrinsic portion of cytochrome f from the, thermophilic cyanobacterium Phormidium laminosum demonstrates that an, unusual buried chain of five water molecules is remarkably conserved, throughout the biological range of cytochrome f from cyanobacteria to, plants [Martinez et al. (1994) Structure 2, 95-105]. Structure and, sequence conservation of the cytochrome f extrinsic portion is, concentrated at the heme, in the buried water chain, and in the vicinity, of the transmembrane helix anchor. The electrostatic surface potential is, variable, so that the surface of P. laminosum cytochrome f is much more, acidic than that from turnip. Cytochrome f is unrelated to cytochrome, c(1), its functional analogue in the mitochondrial respiratory cytochrome, bc(1) complex, although other components of the b(6)f and bc(1) complexes, are homologous. Identical function of the two complexes is inferred for, events taking place at sites of strong sequence conservation. Conserved, sites throughout the entire cytochrome b(6)f/bc(1) family include the, cluster-binding domain of the Rieske protein and the heme b and, quinone-binding sites on the electrochemically positive side of the, membrane within the b cytochrome, but not the putative quinone-binding, site on the electrochemically negative side.
About this Structure
1CI3 is a Single protein structure of sequence from Phormidium laminosum with ZN and HEM as ligands. Full crystallographic information is available from OCA.
Reference
Structure of the soluble domain of cytochrome f from the cyanobacterium Phormidium laminosum., Carrell CJ, Schlarb BG, Bendall DS, Howe CJ, Cramer WA, Smith JL, Biochemistry. 1999 Jul 27;38(30):9590-9. PMID:10423236
Page seeded by OCA on Tue Nov 20 12:28:38 2007
