Rhodobacter sphaeroides absorption spectra

Fig. 10. Absorption spectrum of purified tubular membrane of Rb. sphaeroides at 77 K. The inset shows the dithionite-minus-ferricyanide difference spectrum of the same sample in the cytochrome a-band region. The right side shows results of gel-electrophoresis measurements. See text for discussion. Figure and data source Jungas, Ranck, Rigaud, Joliot and Vermdglio (1999) Supramoiecular organization of the photosynthetic apparatus of Rhodobacter sphaeroides. EMBO J 18 536.

Fig. 9. (A) Absorption spectrum of Rb. sphaeroides used as a reference to show the Qx and Qy bands of the primary donor (P), BChl [B] and bacteriopheophytin [BO] (B) Femtosecond absorption changes at 920 (a), 785 (b) and 545 nm (c) vs. the delay time of the monitoring pulse measured at room temperature, and (C) absorption changes at 920 (a) and 794 nm (b) measured at 25 K. Figure source (A) see Fig. 7 (B) Holzapfel, Finkele, Kaiser, Oesterheldt, Scheer, Stilz and Zinth (1990) Initial electron transferin the reaction center from Rhodobacter sphaeroides. Proc Nat Acad Sci, USA 87 5170 (C) Zinth and Kaiser (1993) Time-resolved spectroscopy of the primary electron transfer in reaction centers of Rhodobacter sphaeroides and Rhodopseudomonas viridis. I n JR Norris and J Deisenhofer (eds) The Photosynthetic Reaction Center, Voi il, p 82. Acad Press.

Fig. 3. (a) Near-infrared absorption spectrum of Rhodobacter sphaeroides reaction centers as a function of temperature, (b) Absorption maximum of the special pair band at 860 nm plotted versus temperature, (c) Line width of the special pair band at 860 nm versus temperature. (From Austin et al " )... 

Fig. 6.7 FTIR difference spectrum (light-minus-dark) of the absorbance changes associated with electron transfer from the special pair of bacteriochlorophylls (P) to a quinone (Qa) in photosynthetic reaction centers of Rhodobacter sphaeroides. The negative absorption changes result mainly from loss of absorption bands of P the positive changes, from the absorption bands of the oxidized dimer (P ). These measurements were made with a thin film of reaction centers at 100 K. The amplitudes are scaled arbitrarily. Adapted from [101]...

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