Bioinorganic Chemistry:
models for metalloenzymes
An important source of information about the structure and mechanism of action of metallobiomolecules is the study of synthetic species that mimic the structure and properties of the corresponding native site.
Crystal structure of PS II
One of these biological systems is Photosystem II (PS II), the enzyme that catalyzes H2O oxidation to O2 in green plants and cyanobacteria. The species responsible for this reaction, called the water oxidizing complex (WOC), is a tetranuclear Mn cluster, with oxide and carboxylate ligation.
Mn4
We have synthesized a number of tetranuclear, oxide bridged, Mn carboxylate complexes involving high oxidation state metal ions to function as synthetic models for the WOC. The 2nd generation models ([Mn4O3X(RCO2)3(dbm)3]) exhibit many of the reactions of the biological system.
We are currently working on a 3rd generation of structural models,
based on the very recent knowledge of the protein’s Mn4 structure.
Mn4-2
3rd generation
models for WOC
Mn4-3