PrepHEnate dependent hYDRoxylations – PHEYDR

In aerobic biological hydroxylations, mono-oxygenases activate molecular oxygen to a peroxy intermediate, using bound cofactors such as heme, flavin or metal ions (Fe, Cu). In anaerobic biological hydroxylations, molybdopterin mono-oxygenases activate a water molecule. We have identified a new type of mono-oxygenases that do not depend on molecular oxygen nor water. The UbiU-UbiV proteins are bacterial enzymes possessing a [4Fe-4S] cluster and perform three hydroxylation reactions on the ubiquinone ring during its anaerobic biosynthesis. Based on strong preliminary results suggesting that the UbiU iron-sulfur cluster activates prephenate, we will combine genetics, biochemistry, biophysics, and organic synthesis to elucidate the unprecedented chemistry of such anaerobic hydroxylation reactions in which prephenate is the sole source of oxygen atom. We will also evaluate the possibility to target UbiU-UbiV proteins from pathogenic bacteria, such as Pseudomonas aeruginosa, for future antimicrobial approaches. Indeed, these proteins do not exist in humans and we propose to synthesize specific UbiU-UbiV inhibitors based on the results of our study of the active site and mechanism of these proteins. These inhibitors will also refine the understanding of the enzymatic mechanism of anaerobic hydroxylation.