Biosynthetic Ca /Sr Exchange in the Photosystem II Oxygen-evolving Enzyme of Thermosynechococcus elongatus*□S
نویسندگان
چکیده
From the ‡Service de Bioénergétique, DBJC, URA CNRS 2096, CEA Saclay, 91191 Gif sur Yvette, France, ¶Institut de Biologie Physico-Chimique, CNRS, UPR 1261, 13 rue Pierre et Marie Curie, 75005 Paris, France, Laboratoire d’Ecologie de la Photosynthèse, DEVM, CEA Cadarache, 13108 Saint Paul lez Durance, France, and **Service de Biophysique des Fonctions Membranaires, DBJC, CEA Saclay, 91191 Gif sur Yvette, France
منابع مشابه
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The active site for water oxidation in photosystem II goes through five sequential oxidation states (S(0) to S(4)) before O(2) is evolved. It consists of a Mn(4)Ca cluster close to a redox-active tyrosine residue (Tyr(Z)). Cl(-) is also required for enzyme activity. To study the role of Ca(2+) and Cl(-) in PSII, these ions were biosynthetically substituted by Sr(2+) and Br(-), respectively, in ...
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