Spectral evidence for cytochrome o in the brown membrane of Halobacterium halobium.

摘要: Abstract The brown membrane domain of Halobacterium halobium is a developmental precursor the purple and it contains b-type cytochrome in addition to bacterio-opsin. In this report we provide spectroscopic evidence that majority content halobacterial o. This has absorption spectral properties oxidized, reduced, CO liganded states which are characteristic CD spectra show complex bilobed pattern Soret region reflects similarity heme environment those other cytochromes involved electron transport. We have also demonstrated positive cooperativity binding which, combined with results, suggests two interacting moieties per o Size exclusion HPLC solubilized preparations shows b containing protein an Mr 42,000–46,000. may be easily separated from bacterio-opsin using hydroxyapatite elution method on Triton X-100 preparations. relative ease disks oriented high optical quality films should make valuable model system for future investigations Cytochrome