Self-assembly and energy transfer in artificial light-harvesting complexes of bacteriochlorophyll c with astaxanthin

0377646 - BC 2013 RIV NL eng J - Journal Article
Alster, J. - Polívka, Tomáš - Arellano, J.B. - Hříbek, P. - Vácha, František - Hala, J. - Pšenčík, J.
Self-assembly and energy transfer in artificial light-harvesting complexes of bacteriochlorophyll c with astaxanthin.
Photosynthesis Research. Roč. 111, 1-2 (2012), s. 193-204. ISSN 0166-8595. E-ISSN 1573-5079
R&D Projects: GA ČR GA206/09/0375
Institutional research plan: CEZ:AV0Z50510513
Keywords : light-harvesting * astaxanthin * self-assembly * bacteriochlorophyll aggregates
Subject RIV: BO - Biophysics
Impact factor: 3.150, year: 2012

The paper reports the self-assembly of bacteriochlorophyll c with the xantophyll astaxanthin, which leads to the formation of a new type of complexes. The results indicate that, due to its specific structure, astaxanthin molecules competes with bacteriochlorophylls for the bonds involved in the aggregation, thus preventing formation of any significant red shift compared to pure bacteriochlorophyll c in aqueous buffer. A strong interaction between both types of pigments in the developed assemblies is manifested by a rather efficient (~40%) excitation energy transfer from astaxanthin to bacteriochlorophyll c, as revealed by fluorescence excitation spectroscopy. Results of transient absorption spectroscopy show that the energy transfer is very fast (<500 fs) and proceeds via the S2 state of astaxanthin.
Permanent Link: http://hdl.handle.net/11104/0209749