Elucidation of active site residues of Arabidopsis thaliana flavonol synthase provides a molecular platform for engineering flavonols

Five residues in Arabidopsis thaliana flavonol synthase, H132, F134, K202, F293 and E295, were identified as potential active site residues via tertiary structure superimposition with A. thaliana anthocyanidin synthase. The importance of these residues in determining the functionality of the enzyme was investigated through a series of site-directed mutagenesis.