Metallo-radical hypothesis for photoassembly of (Mn)4-cluster of photosynthetic oxygen evolving complex.

نویسنده

  • T Ono
چکیده

A new hypothetical mechanism is proposed for photoassembly of the (Mn)4-cluster of the photosynthetic oxygen evolving complex (OEC). In this process, a neutral radical of Y(Z) tyrosine plays a role in oxidizing Mn2+ associated with an apo-OEC, and also in abstracting a proton from a water molecule bound to the Mn2+ ion, together with D1-His190. This is in a similar fashion to the metallo-radical mechanism proposed for photosynthetic water oxidation by the (Mn)4-cluster. The model insists that a common mechanism participates in the photoassembly of the (Mn)4-cluster and the photosynthetic water oxidation.

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عنوان ژورنال:
  • Biochimica et biophysica acta

دوره 1503 1-2  شماره 

صفحات  -

تاریخ انتشار 2001