1ci3
From Proteopedia
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| , resolution 1.900Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | and | ||||||
| Gene: | PETA (Phormidium laminosum) | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
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. 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 Thu Mar 20 10:24:38 2008
