Transition Metal Binding Peptides as Artificial Enzymes

Natural enzymes owe their catalytic activity and high turn over ratios to a two fold catalytic mechanism. First, the enzyme possesses catalytic machinery that efficiently perform the reaction for which the enzyme is constructed. Secondly, substrate specificity is largely obtained through binding and optimal interaction of the substrate with binding pockets of the enzyme. Together these two mechanistic parts lead to high specificities and very high turn over ratios. A similar combination of properties would be highly appreciated in the construction of an artificial enzyme to be used for conversion in organic synthesis. Therefore the SPOCC centre has a program on the synthesis of large peptide libraries, which can bind transition metals to produce catalytically active and specific transition metal peptide complexes on solid support. This is achieved through derivatisation of the peptide with phosphines and carbenes with high potential of ligating to the transition metal. Ru, Pd, Rh and many other catalytic metals can be bound to solid-phase phosphinylated peptide libraries and thereby provides the source of screening for new selective catalysts displaying both regio and stereos selectivity in numerous organic transformations.