J. Phys. Chem. 1989, 93, 7503-7509
7503
Excitation Energy Flow in Chlorosome Antennas of Green Photosynthetic Bacteria Mamoru Mimuro? Tsunenori Nozawa,i Naoto Tamai,O*lKeizou Shimada,ll Iwao Yamazaki,§** National Institute for Basic Biology, Myodaiji, Okazaki. Aichi 444, Japan, Department of Molecular Chemistry and Engineering, Faculty of Engineering, Tohoku University, Aoba, Aramaki, Sendai, Miyagi 980, Japan, Institute for Molecular Science, Myodaiji, Okazaki, Aichi 444, Japan, and Department of Biology, Faculty of Science, Tokyo Metropolitan University, Fukazawa, Setagaya, Tokyo 164, Japan
Su Lin, Robert S. Knox, Department of Physics and Astronomy and the Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14627
Bruce P. Wittmershaus,# Daniel C. Brune, and Robert E. Blankenship*
Downloaded by UNIV OF NEBRASKA-LINCOLN on September 2, 2015 | http://pubs.acs.org Publication Date: October 1, 1989 | doi: 10.1021/j100358a047
Department of Chemistry and the Center for the Study of Early Events in Photosynthesis, Arizona State University, Tempe, Arizona 85287- I604 (Received: February 24, 1989)
Energy flow in whole cells of the thermophilic green photosynthetic bacterium Chlorofexus aurantiacus was studied by measurements of time-resolved fluorescence spectra in the picosecond time range, detected by both streak camera and single-photon counting methods. These data characterize the energy-transfer sequence from bacteriochlorophyll c (BChl c ) , found in membrane-associated antenna structures called chlorosomes, to BChl a in the chlorosome baseplate, then to a BChl a antenna complex in the cytoplasmic membrane, and finally to the photochemical reaction center. Upon selective excitation of BChl c in chlorosomes, the decay time of the emission arising from BChl c was 16 ps. The apparent rise time of the emission from the baseplate pigment was