Chemical complementation identifies a proton acceptor for redox-active tyrosine D in photosystem II
نویسندگان
چکیده
منابع مشابه
Chemical complementation identifies a proton acceptor for redox-active tyrosine D in photosystem II.
Through the use of site-directed mutagenesis and chemical rescue, we have identified the proton acceptor for redox-active tyrosine D in photosystem II (PSII). Effects of chemical rescue on the tyrosyl radical were monitored by EPR spectroscopy. We also have acquired the Fourier-transform infrared (FT-IR) spectrum associated with the oxidation of tyrosine D and concomitant protonation of the acc...
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Photosystem II, the photosynthetic water-oxidizing complex, contains two redox-active tyrosine residues. Although current models suggest that these tyrosines are located in symmetric positions in the reaction center, there are functional differences between them. To elucidate those structural factors that give rise to this functional asymmetry, we have used difference Fourier-transform infrared...
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Thin-layer cell spectroelectrochemistry, featuring rigorous potential control and rapid redox equilibration within the cell, was used to measure the redox potential E(m)(Phe a/Phe a(-)) of pheophytin (Phe) a, the primary electron acceptor in an oxygen-evolving photosystem (PS) II core complex from a thermophilic cyanobacterium Thermosynechococcus elongatus. Interferences from dissolved O(2) and...
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ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 1997
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.94.26.14406