Aldehyde oxidase catalyses the reaction: aldehyde + H2O + O2 = a carboxylic acid + H2O2It contains molybdenum, [2Fe-2S] centres and FAD. It also oxidizes quinoline and pyridine derivatives. It is probably identical to retinal oxidase .Aldehyde oxidase oxidises various aliphatic and aromatic aldehydes using oxygen as an electron acceptor. It has a molecular mass of 132 kDa and consists of three non-identical subunits with molecular masses of 88, 39, and 18 kDa. It belongs to the xanthine oxidase family. This enzyme shows high thermostability.