Počet záznamů: 1

Carotenoids in Energy Transfer and Quenching Processes in Pcb and Pcb-PS I Complexes from Prochlorothrix hollandica

  1. 1.
    0345900 - BC-A 2012 RIV US eng J - Článek v odborném periodiku
    Durchan, Milan - Herbstová, Miroslava - Fuciman, M. - Gardian, Zdenko - Vácha, František - Polívka, Tomáš
    Carotenoids in Energy Transfer and Quenching Processes in Pcb and Pcb-PS I Complexes from Prochlorothrix hollandica.
    Journal of Physical Chemistry B. Roč. 114, č. 28 (2010), s. 9275-9282 ISSN 1520-6106
    Grant CEP: GA AV ČR IAA608170604; GA AV ČR IAA608170603
    Výzkumný záměr: CEZ:AV0Z50510513
    Klíčová slova: carotenoids * oxyphotobacteria * energy transfer
    Kód oboru RIV: BO - Biofyzika
    Impakt faktor: 3.603, rok: 2010

    Chlorophyll (Chl) a/b-binding proteins from Prochlorothrix hollandica known as Pcb antennae were studied by femtosecond transient absorption to identify energy transfer rates and pathways. Carotenoids transfer energy to Chl with low efficiency of ~25% in Pcb complexes. Analysis of transient absorption spectra identified a pathway from the hot S1 state of carotenoids as the major energy transfer channel between whereas the S2 state contributes only marginally to energy transfer. Due to energetic reasons, no energy transfer is possible via the relaxed S1 state of carotenoids. The low overall energy transfer efficiency of carotenoids recognizes chlorophylls as the main light-harvesting pigments. Besides Chl a, presence of Chl b, which transfers energy to Chl a with nearly 100% efficiency, significantly broadens the spectral range accessible for light-harvesting and improves cross-section of Pcb complexes. The major role of carotenoids in Pcb is photoprotection.
    Trvalý link: http://hdl.handle.net/11104/0005962