Bridged Bimetallic Enzymes Are 2 heads better than 1?

We hypothesize that the unique bridged bimetallic center functions as a "superelectrophile" in a possible electrocyclic hydride transfer reaction. Our aim is to determine how this center functions, by carrying out combined quantum mechanics/molecular dynamics simulations of the reaction pathway. Our second aim is to continue our crystallographic studies of the overall mechanism by probing the role of the metal ions through site-directed mutagenesis followed by direct crystallographic observation of the Michaelis complex with sugar substrates. We use these structures to test the hypothesis that communication between the metal ions, in the form of the bridge, is essential for proper functioning of the center in hydride transfer catalysis.


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