Low-Temperature Spectroscopic Properties of the Peridinin鈥揅hlorophyll a鈥揚rotein (PCP) Complex from the Coral Symbiotic Dinoflagellate Symbiodinium

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• 作者：Dariusz M. Niedzwiedzki ; Jing Jiang ; Cynthia S. Lo ; Robert E. Blankenship
• 刊名：Journal of Physical Chemistry B
• 出版年：2013
• 出版时间：September 26, 2013
• 年：2013
• 卷：117
• 期：38
• 页码：11091-11099
• 全文大小：489K
• 年卷期：v.117,no.38(September 26, 2013)
• ISSN：1520-5207

文摘

The spectroscopic properties of the peridinin鈥揷hlorophyll a鈥損rotein (PCP) from the coral symbiotic dinoflagellate Symbiodinium have been characterized by application of various ultrafast optical spectroscopies including femto- and nanosecond time-resolved absorption and picosecond time-resolved fluorescence (TRF) at 77 K. Excited state properties of peridinin and Chl a and their intramolecular interaction characteristics have been obtained from global fitting analysis and directed kinetic modeling of the data sets and compared to their counterparts known for the PCP from Amphidinium carterae. The lifetimes of the excited state of peridinin show close agreement with those known for the counterpart PCP, demonstrating that molecular interactions have the same characteristics in both complexes. More variances have been recorded for the excited state properties of Chl a including elongation of both the intramolecular energy transfer time between Chl鈥檚 within the pair in the protein monomer and the excited state lifetime of the long wavelength form of Chl a (terminal acceptor). Kinetic modeling of formation of the peridinin triplet state has shown that the PCP is protected from potential photodamage due to an extremely fast peridinin triplet state formation of k_TT = (14.4 卤 2.3) 脳 10⁹ s^鈥? ((70 卤 12)^鈭? (ps)^鈭?) that guarantees instantaneous depletion of Chl a triplets and prevents formation of harmful singlet oxygen (¹螖_gO₂).