Abstract
Our project is focused on studies of ultrafast energy transfer from carotenoid to BChl in LH1 complexes. It is known that photosynthetic LH1 complex devoid of carotenoids dissociates into B820 and B780 subunit forms in the presence of detergent. B820 subunit consisting of dimeric BChl a was isolated from carotenoid-less mutant Rhodospirillum rubrum G9 strain using a mild detergent β-OG and purified by ion-exchange chromatography on DEAE-cellulose. The subunits bind carotenoid molecules (e.g. anhydrorhodovibrin) and form carotenoid-containing complex. In the reconstituted complex BChl main absorption peak (Qy) undergoes a large red-shift and has a maximum at 880 nm, as in the native LH1 antenna. The reconstituted complexes having various carotenoids will be investigated by fluorescence and femto-second absorption spectroscopy.
