title: The orientation of the three haems of the 'in situ' ubiquinol oxidase, cytochrome bd, of Escherichia coli.
abstract: The Escherichia coli cytochrome bd complex incorporates three haems as prosthetic groups. In the ferric form these are a predominantly high-spin chlorin (haem d), a high-spin haem b (b595) and a low-spin haem b (b558). The orientations of these three haems have been determined by e.p.r. studies on oriented multilayer preparations of cytoplasmic membrane fragments. The low-spin haem b (b558) and the high-spin haem d are oriented with their haem planes perpendicular to the membrane plane. The high-spin haem b595 is oriented with its haem plane at approx. 55 degrees to the membrane plane. A minor low-spin component, attributable to a low-spin subpopulation of the haem d, is also oriented with its haem plane perpendicular to the membrane plane.
authors.affiliation: Department of Biochemistry and Microbiology, University of St. Andrews, Fife, Scotland, U.K.
authors.forename: W J
authors.initials: WJ
authors.lastname: Ingledew
authors.forename: R A
authors.initials: RA
authors.lastname: Rothery
authors.forename: R B
authors.initials: RB
authors.lastname: Gennis
authors.forename: J C
authors.initials: JC
authors.lastname: Salerno
mesh_terms: D001665:Binding Sites; D002462:Cell Membrane / Q000201:enzymology; D003573:Cytochrome b Group; D003580:Cytochromes / Q000737:chemistry*; D004578:Electron Spin Resonance Spectroscopy; D045222:Electron Transport Chain Complex Proteins; D004926:Escherichia coli / Q000201:enzymology*; D029968:Escherichia coli Proteins; D006418:Heme / Q000032:analysis*; D010088:Oxidoreductases / Q000737:chemistry*; D011487:Protein Conformation
chemical_list: D003573:Cytochrome b Group; D003580:Cytochromes; D045222:Electron Transport Chain Complex Proteins; D029968:Escherichia coli Proteins; D006418:Heme; D010088:Oxidoreductases; C040077:cytochrome bd terminal oxidase complex, E coli