Regulating the Energy Flow in a Cyanobacterial Light Harvesting Antenna Complex

do Eisenberg; Felipe Caycedo-Soler; Dvir Harris; Shira Yochelis; Susana F. Huelga; Martin B. Plenio; Noam Adir; Nir Keren; Yossi Paltiel

doi:10.1021/acs.jpcb.6b10590

arXiv · 1707.00817

Regulating the Energy Flow in a Cyanobacterial Light Harvesting Antenna Complex

do Eisenberg·Felipe Caycedo-Soler·Dvir Harris·Shira Yochelis·Susana F. Huelga·Martin B. Plenio·Noam Adir·Nir Keren·Yossi Paltiel

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Abstract

Photosynthetic organisms harvest light energy, utilizing the absorption and energy transfer properties of protein-bound chromophores. Controlling the harvesting efficiency is critical for the optimal function of the photosynthetic apparatus. Here, we show that cyanobacterial light-harvesting antenna may be able to regulate the flow of energy in order to switch reversibly from efficient energy conversion to photo-protective quenching via a structural change. We isolated cyanobacterial light harvesting proteins, phycocyanin and allophycocyanin, and measured their optical properties in solution and in an aggregated-desiccated state. The results indicate that energy band structures are changed, generating a switch between two modes of operation: exciton transfer and quenching; achieved without dedicated carotenoid quenchers. This flexibility can contribute greatly to the large dynamic range of cyanobacterial light harvesting systems.

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do Eisenberg, Felipe Caycedo-Soler, Dvir Harris, Shira Yochelis, Susana F. Huelga, Martin B. Plenio, Noam Adir, Nir Keren, Yossi Paltiel. 2017-07-04. Regulating the Energy Flow in a Cyanobacterial Light Harvesting Antenna Complex. https://doi.org/10.1021/acs.jpcb.6b10590

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