The effects of detergents DDM and beta-OG on the singlet excited state lifetime of the chlorophyll a in cytochrome b6f complex from spinach chloroplasts.
The effects of detergents DDM and β-OG on the singlet excited state lifetime of the chlorophyll a in cytochrome b6f complex from spinach chloroplasts

The singlet excited state lifetime of the chlorophyll a (Chl a) in cytochrome b 6 f (Cyt b 6 f) complex was reported to be shorter than that of free Chl a in methanol, but the value was different for Cyt b 6 f complexes from different sources (～200 and ～600 ps are the two measured results). The present study demonstrated that the singlet excited state lifetime is associated with the detergents n-dodecyl-β-D-maltoside (DDM) and n-octyl-β-D-glucopyranoside (β-OG), but has nothing to do with the different sources of Cyt b 6 f complexes. Compared with the Cyt b 6 f dissolved in β-OG, the Cyt b 6 f in DDM had a lower fluorescence yield, a lower photodegradation rate of Chl a, and a shorter lifetime of Chl a excited state. In short, the singlet excited state lifetime, ～200 ps, of the Chl a in Cyt b 6 f complex in DDM is closer to the true in vivo. Supported by the National Natural Science Foundation of China (Grant Nos. 39890390 and 20673144)