1.3.1.105 crystallisation in complex with NADPH and 4-hydroxy-2,5-dimethyl-3(2H)-furanone or in complex with NADPH and 4-hydroxy-5-methyl-3(2H)-furanone. The crystal structure of FaEO was solved by molecular replacement using a published X-ray structure of a quinone oxidoreductase from Thermus thermophilus. The structure belongs to the zinc-independent medium chain dehydrogenase/reductase family 722809