The Arabidopsis (Arabidopsis thaliana) aldehyde oxidases are a multigene family of four oxidases (AAO1–AAO4) that oxidize a variety of aldehydes, among them abscisic aldehyde, which is oxidized to the phytohormone abscisic acid. Toxic aldehydes are generated in plants both under normal conditions and in response to stress. The detoxification of such aldehydes by oxidation is attributed to aldeh...

1. We have previously described C8-substituted pyrido[3,4-d]pyrimidin-4(3H)-one derivatives as cell permeable inhibitors of the KDM4 and KDM5 subfamilies of JmjC histone lysine demethylases. 2. Although exemplar compound 1 exhibited moderate clearance in mouse liver microsomes, it was highly cleared in vivo due to metabolism by aldehyde oxidase (AO). Similar human and mouse AO-mediated metaboli...

The reduction of aldehyde oxidase (EC 1.2.3.1) by the substrate W-methylnicotinamide under anaerobic conditions is a biphasic reaction. In the present work we present evidence that this behavior is due to the presence, in standard preparations, of active and inactive enzyme, the former being responsible for the fast reaction and differing from the latter by the presence of a persulfide group. I...