Spectroscopic characterization of a novel multiheme c-type cytochrome widely implicated in bacterial electron transport.
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.
Roldán
M D
MD
School of Biological Sciences, Centre for Metalloprotein Spectroscopy and Biology, University of East Anglia, Norwich, UK.
Sears
H J
HJ
Cheesman
M R
MR
Ferguson
S J
SJ
Thomson
A J
AJ
Berks
B C
BC
Richardson
D J
DJ
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
D003574:Cytochrome c Group; D017931:DNA Primers