Is an essential component of the ethanol oxidation system that allows P.aeruginosa to grow on ethanol as the sole carbon and energy source. Is the direct electron acceptor of the quinoprotein ethanol dehydrogenase (QEDH). E(0) is 280 mV. Alcohol metabolism; ethanol degradation; acetate from ethanol. Monomer (PubMed:8380982). Interacts with the quinoprotein ethanol dehydrogenase (QEDH) ExaA (PubMed:19224199). Induced by growth on ethanol. Binds 1 heme group per subunit. Cells lacking this gene are completely unable to grow on ethanol as the sole carbon source.