Spectroscopic studies of bound cytochrome c and an iron-sulfur center in a purified reaction center complex from the green sulfur bacterium Chlorobium tepidum

Publisher Website
Google Scholar
Abstract
Flash-induced optical kinetics at room temperature of cytochrome (Cyt) c 551 and an Fe-S center (CFA/CFB) bound to a purified reaction center (RC) complex from the green sulfur photosynthetic bacterium Chlorobium tepidum were studied. At 551 nm, the flash-induced absorbance change decayed with a t 1/2 of several hundred ms, and the decay was accelerated by 1-methoxy-5-methylphenazinium methyl sulfate (mPMS). In the blue region, the absorbance change was composed of mPMS-dependent (Cyt) and mPMS-independent component (CFA/CFB) which decayed with a t 1/2 of ∼400–650 ms. Decay of the latter was effectively accelerated by benzyl viologen (Em −360 mV) and methyl viologen (−440 mV), and less effectively by triquat (−540 mV). The difference spectrum of Cyt c had negative peaks at 551, ∼520 and ∼420 nm, with a positive rise at ∼440 to ∼500 nm. The difference spectrum of CFA/CFB resembled P430 of PSI, and had a broad negative peak at 430∼435 nm.

This publication has 27 references indexed in Scilit: