The detection and characterization by electron-paramagnetic-resonance spectroscopy of iron-sulphur proteins and other electron-transport components in chromatophores from the purple bacterium Chromatium.

摘要: Low-temperature e.p.r. (electron-paramagnetic-resonance) spectroscopy was used to detect electron-transport components in Chromatium chromatophores with signals the g =2.00 region. High-potential iron protein ( E m8.0 =+325mV, where is midpoint potential at pH8) and a second component =1.90, =+285mV) are oxidized illuminated chromatophores. Two iron–sulphur proteins =1.94) =−290mV =−50mV present. One =−50mV) reduced on illumination. A =1.82) =−135mV photoreduced 10°K. The of this altered by o -phenanthroline pH. properties suggest that it primary electron acceptor photochemical system. Another =1.98) also has some acceptor, but its function cannot be completely defined. These results show present system indicate their role transport.