title: Pseudospecific docking surfaces on electron transfer proteins as illustrated by pseudoazurin, cytochrome c550 and cytochrome cd1 nitrite reductase.
abstract: The structure of pseudoazurin from Thiosphaera pantotropha has been determined and compared to structures of both soluble and membrane-bound periplasmic redox proteins. The results show a matching set of unipolar, but promiscuous, docking motifs based on a positive hydrophobic surface patch on the electron shuttle proteins pseudoazurin and cytochrome c550 and a negative hydrophobic patch on the surface of their known redox partners. The observed electrostatic handedness is argued to be associated with the charge-asymmetry of the membrane-bound components of the redox chain due to von Heijne's 'positives-inside' principle. We propose a 'positives-in-between' rule for electron shuttle proteins, and expect a negative hydrophobic patch to be present on both the highest and lowest redox potential species in a series of electron carriers.
authors.affiliation: Laboratory of Molecular Biophysics, University of Oxford, UK.
authors.forename: P A
authors.initials: PA
authors.lastname: Williams
authors.forename: V
authors.initials: V
authors.lastname: Fülöp
authors.forename: Y C
authors.initials: YC
authors.lastname: Leung
authors.forename: C
authors.initials: C
authors.lastname: Chan
authors.forename: J W
authors.initials: JW
authors.lastname: Moir
authors.forename: G
authors.initials: G
authors.lastname: Howlett
authors.forename: S J
authors.initials: SJ
authors.lastname: Ferguson
authors.forename: S E
authors.initials: SE
authors.lastname: Radford
authors.forename: J
authors.initials: J
authors.lastname: Hajdu
mesh_terms: D001400:Azurin / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism; D018360:Crystallography, X-Ray; D003574:Cytochrome c Group / Q000737:chemistry / Q000378:metabolism; D003580:Cytochromes / Q000737:chemistry / Q000378:metabolism; D004579:Electron Transport; D006091:Gram-Negative Chemolithotrophic Bacteria / Q000737:chemistry; D008958:Models, Molecular; D009572:Nitrite Reductases / Q000737:chemistry / Q000378:metabolism; D011487:Protein Conformation
chemical_list: D003574:Cytochrome c Group; D003580:Cytochromes; C047163:pseudoazurin; D001400:Azurin; C019315:cytochrome cd1; C031732:cytochrome C-550; D009572:Nitrite Reductases