mixed function oxidase

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mixed function oxidase An enzyme complex found in animals that oxidizes toxic compounds to render them more susceptible to metabolism and excretion. Such complexes are induced in a wide range of species following exposure to toxic organic substances, such as alkaloids, phenolics, terpenoids, and quinones. The enzymes are localized in the liver in vertebrates and in similar tissues, such as the hepatopancreas, in invertebrates. They catalyse the introduction to the toxic molecule of single oxygen atoms in the form of hydroxyl groups, which requires energy. High levels of these enzymes occur in plant-eating insects, in which they detoxify the natural toxins of the plants. Such enzymes may also render insects more resistant to insecticides.