Photochem Photobiol Sci
November 2024
Perovskite quantum dots (pQDs) have gathered a lot of attention because of their outstanding optoelectronic properties. Photoswitchable pQDs have the potential for application in single particle optical memories and bio-imaging. Hybrids of photochromic diarylethenes (DAE) and pQDs show a luminescence photoswitching property, however, the cycle stability in such systems is low because of photoinduced electron transfer (PET) from pQDs to DAE.
View Article and Find Full Text PDFCyanobacterial photosynthetic apparatus efficiently capture sunlight, and the energy is subsequently transferred to photosystem I (PSI) and II (PSII), to produce electrochemical potentials. PSII is a unique membrane protein complex that photo-catalyzes oxidation of water and majorly contains photosynthetic pigments of chlorophyll a and carotenoids. In the present study, the ultrafast energy transfer and charge separation dynamics of PSII from a thermophilic cyanobacterium Thermosynechococcus vulcanus were reinvestigated by femtosecond pump-probe spectroscopic measurements under low temperature and weak intensity excitation condition.
View Article and Find Full Text PDFWe previously identified Xenopus tudor domain containing 6/Xenopus tudor repeat (Xtdrd6/Xtr), which was exclusively expressed in the germ cells of adult Xenopus laevis. Western blot analysis showed that the XTdrd6/Xtr protein was translated in St. I/II oocytes and persisted as a maternal factor until the tailbud stage.
View Article and Find Full Text PDFisomers of carotenoids play important roles in light harvesting and photoprotection in photosynthetic bacteria, such as the reaction center in purple bacteria and the photosynthetic apparatus in cyanobacteria. Carotenoids containing carbonyl groups are involved in efficient energy transfer to chlorophyll in light-harvesting complexes, and their intramolecular charge-transfer (ICT) excited states are known to be important for this process. Previous studies, using ultrafast laser spectroscopy, have focused on the central- isomer of carbonyl-containing carotenoids, revealing that the ICT excited state is stabilized in polar environments.
View Article and Find Full Text PDFIn bacterial photosynthesis, the excitation energy transfer (EET) from carotenoids to bacteriochlorophyll a has a significant impact on the overall efficiency of the primary photosynthetic process. This efficiency can be enhanced when the involved carotenoid has intramolecular charge-transfer (ICT) character, as found in light-harvesting systems of marine alga and diatoms. Here, we provide insights into the significance of ICT excited states following the incorporation of a higher plant carotenoid, β-apo-8'-carotenal, into the carotenoidless light-harvesting 1 (LH1) complex of the purple photosynthetic bacterium Rhodospirillum rubrum strain G9+.
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