Concerted hydrogen-atom abstraction in photosynthetic water oxidation. Academic Article

abstract

• Photosystem II evolves oxygen by using water in the unlikely role of a reductant. The absorption of sunlight by chlorophyll produces highly oxidizing equivalents that are filled with electrons stripped from water. This proton-coupled redox chemistry occurs at the oxygen-evolving complex, which contains a tetramanganese cluster, a redox-active tyrosine amino acid hydrogen-bonded to a histidine amino acid, a calcium ion and chloride. Hydrogen-atom abstraction by the tyrosyl radical from water bound to the manganese cluster is now widely held to occur in this process, at least for some of the steps in the catalytic cycle. We discuss kinetic and energetic constraints on the hydrogen-atom abstraction process.

authors

• Tommos, Cecilia

published proceedings

• Curr Opin Plant Biol

author list (cited authors)

• Westphal, K. L., Tommos, C., Cukier, R. I., & Babcock, G. T.

complete list of authors

• Westphal, KL||Tommos, C||Cukier, RI||Babcock, GT

publication date

• June 2000

publisher

• Elsevier  Publisher

published in

• Current Opinion in Plant Biology  Journal

keywords

• Hydrogen
• Kinetics
• Oxidation-Reduction
• Photolysis
• Photosynthesis
• Thermodynamics
• Water

PubMed Central ID

• 10837268

Digital Object Identifier (DOI)

• 10.1016/s1369-5266(00)80071-0

start page

• 236

end page

• 242

volume

• 3

issue

• 3

URL

• http://dx.doi.org/10.1016/s1369-5266(00)80071-0