cytochrome b5 reductase


cy·to·chrome b5 re·duc·tase

(sī'tō-krōm rē-dŭk'tās), A flavoenzyme catalyzing the reduction of two molecules of ferricytochrome b5 to two molecules of ferrocytochrome b5 at the expense of NADH; has a role in fatty acid desaturation; a deficiency can lead to hereditary methemoglobinemia (type I, only observed in erythrocyte cytosol; type II, deficiency in all tissues; type III, deficiency in all hematopoetic cells).