In enzymology, a carbon-monoxide dehydrogenase (cytochrome b-561) () is an enzyme that catalyzes the chemical reaction CO + H2O + 2 ferricytochrome b-561 CO2 + 2 H+ + 2 ferrocytochrome b-561 The 3 substrates of this enzyme are CO, H2O, and ferricytochrome b-561, whereas its 3 products are CO2, H+, and ferrocytochrome b-561. This enzyme belongs to the family of oxidoreductases, specifically those acting on the aldehyde or oxo group of donor with a cytochrome as acceptor. The systematic name of this enzyme class is carbon monoxide,water:cytochrome b-561 oxidoreductase. Other names in common use include carbon monoxide oxidase, carbon monoxide oxygenase (cytochrome b-561), carbon monoxide:methylene blue oxidoreductase, CO dehydrogenase, and carbon-monoxide dehydrogenase. References EC 1.2.2 Enzymes of unknown structure Carbon monoxide