States Of Bacteriochlorophyll Research Articles

2E1430 円偏光二色性と磁気円偏光二色性によるバクテリオクロロフィルcが形成する中間会合体と固相状態の解析

2E1430 円偏光二色性と磁気円偏光二色性によるバクテリオクロロフィルcが形成する中間会合体と固相状態の解析

Time-Resolved Spectral Investigation of Bacteriochlorophyll a and Its Transmetalated Derivatives [Zn]-Bacteriochlorophyll a and [Pd]-Bacteriochlorophyll a

The lowest excited singlet (S1) and triplet (T1) states of bacteriochlorophyll a (BChl) and its central metal derivatives [Zn]- and [Pd]- BChl were investigated by femtosecond time-resolved absorpt...

Pulsed ENDOR of the photoexcited triplet states of bacteriochlorophyll a and of the primary donor P865 in reaction centers of Rhodobacter sphaeroides R-26

The photoexcited triplet states of bacteriochlorophyll a, 3BChl a, and of the primary donor in reaction centers of Rhodobacter sphaeroides R-26, 3P865, are investigated by pulsed EPR and ENDOR spectroscopy. In 3P865 a splitting of ENDOR lines and reduction of corresponding positive and negative hyperfine couplings as compared with the monomeric 3BChl a is observed. This indicates an asymmetric distribution of the triplet excitation over the two BChl a moieties, PL and PM, forming 3P865. Based on the signs of the hyperfine couplings and on a comparison with the cation and anion radical of BChl a an assignment to nuclei in the different dimer halves is proposed. This yields an estimate for the extent of delocalization of the triplet excitation over PL and PM and for the charge transfer contribution of 3P865.

Studies on bacterial chromatophores. II. Energy transfer and photooxidative bleaching of bacteriochlorophyll in relation to structure in normal and carotenoid-depleted Chromatium.

Electronic energy transfer, fluorescence emission spectra and photooxidative bleaching of bacteriochlorophyll in Chromatium chromatophores were shown to be affected by detergent action and by inhibition of normal carotenoid synthesis in the parent cells. These phenomena are discussed in relation to the structure of the chromatophore and the state of bacteriochlorophyll in vivo. A structural role for carotenoids is suggested.