Carbon monoxide is an extremely poisonous gas. Breathing air that contains as little as 0.1% carbon monoxide by volume can be fatal; a concentration of about 1% can cause death within a few minutes. The gas is especially dangerous because it is not easily detected by human senses. Early symptoms of carbon monoxide poisoning include drowsiness and headache, followed by unconsciousness, respiratory failure, and death. First aid for a victim of carbon monoxide poisoning requires access to fresh air; administration of artificial respiration and, if available, oxygen; and, as soon as possible, expert medical attention. When carbon monoxide is inhaled, it reacts with hemoglobin, the red blood pigment that normally carries oxygen to all parts of the body. Because carbon monoxide is attracted to the hemoglobin about 210 times as strongly as is oxygen, it takes the place of oxygen in the blood, causing oxygen starvation throughout the body. Carbon monoxide detectors for homes are now readily available.
Carbon monoxide from automobile and industrial emissions is a dangerous pollutant that may contribute to the greenhouse effect and global warming. In urban areas carbon monoxide, along with aldehydes, react photochemically to produce peroxy radicals. Peroxy radicals react with nitrogen oxide to increase the ratio of NO2 to NO, which reduces the quantity of NO that is available to react with ozone (see smog). Carbon monoxide is also a constituent of tobacco smoke.
Inorganic compound, a highly toxic, colourless, odourless, flammable gas, chemical formula CO. It is produced when carbon (including coal and coke) or carbon-containing fuel (including petroleum hydrocarbons; e.g., gasoline, fuel oil) does not burn completely to carbon dioxide, because of insufficient oxygen. CO is present in the exhaust gases of internal combustion engines and furnaces. It is toxic because it binds to hemoglobin in blood much more strongly than does oxygen and thus interferes with transport of oxygen from lungs to tissues (see hypoxia; respiration). Symptoms of CO poisoning range from headache, nausea, and syncope to coma, weak pulse, respiratory failure, and death. CO is used industrially as a fuel and in synthesis of numerous organic compounds, including methanol, ethylene, and aldehydes.
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This enzyme belongs to the family of oxidoreductases, specifically those acting on the aldehyde or oxo group of donor with other acceptors. The systematic name of this enzyme class is carbon-monoxide:acceptor oxidoreductase. Other names in common use include anaerobic carbon monoxide dehydrogenase, carbon monoxide oxygenase, carbon-monoxide dehydrogenase, and carbon-monoxide:(acceptor) oxidoreductase. This enzyme participates in methane metabolism. It has 4 cofactors: iron, Zinc, Nickel, and Iron-sulfur.