Rieske non-haem dioxygenases are enzymes achieving selective oxidation of substrates. Nature has two different strategies to achieve this selectivity either by size and shape or substrate orientation. Part of this specificity arises from a sieve -like structure called tunnel that hampers the access of certain molecules to the active site of an enzyme. These tunnels are formed by loop-like structures.
In our paper we have been introducing or deleting several amino acids residues to modulate these loops. However, the active site as well as the core of the protein structure is untouched. These drastic modifications emulate the specificity of biological oxidations and result in increased activity and altered selectivity as well as a broadening substrate scope. First analysis of these enzyme variants points towards an altered tunnel geometry and chemists might find inspiration in designing catalysts.
Nature Communications volume 12, Article number: 1095 (2021) DOI 10.1038/s41467-021-21328-8.