It is my pleasure to announce that our paper on the structure of Aldehyde oxidoreductase (AOR) from Aromatoleum aromaticum has been published in Science Advances. The paper is the opus magnum of Agnieszka Winiarska and the result of her cooperation with Marburg University and Max Planck Institute of Biophysics, Frankfurt am Main.
AORs are tungsten enzymes catalysing the oxidation of many different aldehydes to the corresponding carboxylic acids. In contrast to other known AORs, the enzyme from the denitrifying betaproteobacterium Aromatoleum aromaticum consists of three different subunits (AorABC) and utilizes NAD+ as an electron acceptor. In the paper, we reveal that the enzyme forms filaments of repeating AorAB protomers, which are capped by a single NAD-binding AorC subunit, based on solving its structure via cryo-electron microscopy.
Fig. 1. Hypothetical reconstruction of enzyme nanowire based on cryo-em and mass photometry.
Our structure further reveals the binding mode of the native substrate benzoate in the AorB active site. This, together with QM:MM-based modelling for the coordination of the W-co, enables the formulation of catalytic mechanism hypothesis that paves the way for further engineering of AOR for applications in synthetic biology and biotechnology.