CsmA Protein is Associated with BChl a in the Baseplate Subantenna of Chlorosomes of the Green Photosynthetic Bacterium Oscillochloris Trichoides Belonging to the Family Oscillochloridaceae
The idea of association of bacteriochlorophyll a (BChl a) with protein in chlorosomes of the photosynthetic green anoxy genie filamentous bacterium Osc.trichoides, member of the family Oscillochloridaceae, was probed by low-temperature fluorescence spectroscopy and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis of alkaline-treated and untreated chlorosomes. Alkaline treatment of Osc.trichoides chlorosomes resulted in disappearance of BChl a band in their fluorescence spectra. The determination of BChl c and BChl a content confirmed the removal of BChl a from Osc.trichoides chlorosomes upon alkaline treatment. Based on the data obtained, we concluded that alkaline treatment of chlorosomes destroys the BChl a in the baseplate while leaving BChl c in a form that is spectrally indistinguishable from that in untreated chlorosomes. It was shown that upon alkaline treatment, only the S.7 kDa CsmA protein was removed from the chlorosomes among five proteins detected by SDS-PAGE analysis, concomitantly with the disappearance of BChl a fluorescence emission. Based on these results, we suggest that CsmA protein is associated with BChl a in the baseplate subantenna in the chlorosomes of the photosynthetic green bacterium Osc. Trichoides. Comparison of the data for the three families of green photosynthetic bacteria is relevant to assessing the universal principles of optimal antenna organization preserved in evolution despite marked changes in antenna size and structure.
Oscillochloridaceae Chlorosome Baseplate Bacteriochlorophylls a and c CsmA protein
Alexandra S Taisova Anastasiya V Zobova Eugeney P Lukashev Nataliya V Fedorova Zoya G Fetisova
A.N. Belozersky Institute of Physico-Chemical Biology, M.V. Lomonosov Moscow State University Department of Biophysics,M.V. Lomonosov Moscow State University, Moscow 119991, Russian Federation
国际会议
15th International Conference on Photosynthesis(第15届国际光合作用大会)
北京
英文
117-120
2010-08-22（万方平台首次上网日期，不代表论文的发表时间）