Manganese cluster in photosynthesis: Where plants oxidize water to dioxygen
- Lawrence Berkeley National Lab., CA (United States). Structural Biology Div.
The essential involvement of manganese in photosynthetic water oxidation was implicit in the observation by Pirson in 1937 that plants and algae deprived of Mn in their growth medium lost the ability to evolve O{sub 2}. Addition of this essential element to the growth medium resulted in the restoration of water oxidation within 30 min. There is increased interest in the study of Mn in biological chemistry and dioxygen metabolism in the last two decades with the discovery of several Mn redox enzymes. The list of enzymes where Mn is required for redox activity includes a Mn superoxide dismutase, a binuclear Mn-containing catalase, a binuclear Mn-containing ribonucleotide reductase, a proposed binuclear Mn site in thiosulfate oxidase, a Mn peroxidase that is capable of oxidative degradation of lignin, and perhaps the most complex and important, the tetranuclear Mn-containing oxygen-evolving complex in photosystem II (Mn-OEC). Mn is well suited for the redox role with accessible oxidation states of II, III, and IV, and possibly V: oxidation states that have all been proposed to explain the mechanisms of the Mn redox enzymes.
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC03-76SF00098
- OSTI ID:
- 415596
- Journal Information:
- Chemical Reviews, Vol. 96, Issue 7; Other Information: PBD: Nov 1996
- Country of Publication:
- United States
- Language:
- English
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