Energy transfer processes in Rhodopseudomonas palustris grown under low‐light conditions

FEBS Letters

Yamazaki, Iwao³  Nishimura, Yoshinobu³  Shimada, Keizo²  Mimuro, Mamoru¹ 

[1] Natlonal Institute for Basic Biology, Myodaiji, Okazaki, Aichi 444, Japan;Department of Biology, Faculty of Science, Tokyo Metropolitan University, Hachioji, Tokyo 192-03, Japan;Department of Chemical Process Engineering, Faculty of Engineering, Hokkaido University, Sapporo 060, Japan

关键词: Bacteriochlorophyll;    Energy transfer;    Picosecond spectroscopy;    Pigment system;    Photosynthesis;    Rhodopseudomonas palustris;    B803 or F833;    a representative expression of bacteriochlorophyll forms or fluorescence components located at 803 or 833 nm;    LH;    light-harvesting complex;    PAGE;    polyacrylamide gel electrophoresis;   

DOI  :  10.1016/0014-5793(93)80245-P

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Excitation energy flow in the purple photosynthetic bacterium Rhodopseudomonas palustris grown under a low-light intensity was studied by time-resolved fluorescence spectroscopy in the ps time range. This bacterium synthesized the B824 component under this light condition. Time-resolved spectra at 20°C indicated the sequential energy flow in the order of B803, B856, B882 and B900, long wavelength antenna. An emission from B803 was not observed. A remarkable feature was the emission from B824 throughout the measuring time. After the excitation pulse of 100 ps, the spectra did not change any further, indicating the establishment of an equilibrium among components. Based on the energy distribution after equilibrium, parallel energy transfer pathways to LH 1 were suggested; one including B824 integrated in the B803-824-856 complex, and the other, from the B803-856 complex to B882. The latter was the dominant energy flow pathway in this bacterium.

【 授权许可】

Unknown