BackgroundEnoyl-CoA hydratase (MAOC) is required for the biosynthesis of the fatty acid-derive side chains of the ascaroside via peroxisome β-oxidation in the free-living nematode Caenorhabditis elegans. The derivative of dideoxy-sugar, ascarylose is used as dauer pheromones or daumones to induce development of the stress-resistant dauer larvae stage.