Synthesis of Mono‐ and Dihydroxylated Amino Acids with New α‐Ketoglutarate‐Dependent Dioxygenases: Biocatalytic Oxidation of CH Bonds

Iron(II)/$\alpha$-ketoacid-dependent oxygenases ($\alpha$KAOs) are enzymes that mainly catalyse hydroxylation reaction. By using a genomic approach combining sequence comparison and protein-domain sharing, a set of 131 $\alpha$KAO enzymes was prepared. The screening of various substrates revealed five new $\alpha$KAOs. Four $\alpha$KAOs were found to be active towards L-lysine, L-ornithine and L-arginine with total regio- and stereoselectivities and yielding the corresponding 3- or 4-hydroxyamino acids. The enzymatic cascade reaction with two stereoselective regiodivergent $\alpha$ KAOs enabled the synthesis of 3,4-dihydroxy-L- lysine.