title: Spectroscopic characterization of a novel multiheme c-type cytochrome widely implicated in bacterial electron transport.
abstract: NapC is a member of a family of bacterial membrane-anchored tetra-heme c-type cytochromes that participate in a number of respiratory electron transport pathways. They are postulated to mediate electron transfer between membrane quinols/quinones and soluble periplasmic enzymes. The water-soluble heme domain of NapC has been expressed as a periplasmic protein. Mediated redox potentiometry and characterization by UV-visible, magnetic circular dichroism, and electron paramagnetic resonance spectroscopies demonstrates that soluble NapC contains four low spin hemes, each with bis-histidine axial ligation and with midpoint reduction potentials of -56, -181, -207, and -235 mV.
authors.affiliation: School of Biological Sciences, Centre for Metalloprotein Spectroscopy and Biology, University of East Anglia, Norwich, UK.
authors.forename: M D
authors.initials: MD
authors.lastname: Roldán
authors.forename: H J
authors.initials: HJ
authors.lastname: Sears
authors.forename: M R
authors.initials: MR
authors.lastname: Cheesman
authors.forename: S J
authors.initials: SJ
authors.lastname: Ferguson
authors.forename: A J
authors.initials: AJ
authors.lastname: Thomson
authors.forename: B C
authors.initials: BC
authors.lastname: Berks
authors.forename: D J
authors.initials: DJ
authors.lastname: Richardson
mesh_terms: D000595:Amino Acid Sequence; D001419:Bacteria / Q000201:enzymology*; D001483:Base Sequence; D003574:Cytochrome c Group / Q000737:chemistry* / Q000378:metabolism; D017931:DNA Primers; D004579:Electron Transport; D008969:Molecular Sequence Data; D011199:Potentiometry; D017386:Sequence Homology, Amino Acid; D013057:Spectrum Analysis
chemical_list: D003574:Cytochrome c Group; D017931:DNA Primers