It is disclosed herein that microperoxidases are capable of binding carbon monoxide (CO) with high affinity and displacing CO from hemoglobin, thereby acting as CO scavengers. The present disclosure provides methods of treating carboxyhemoglobinemia (or CO poisoning) in a subject by administering a therapeutically amount of an isolated or recombinant microperoxidase. Methods of removing CO from hemoglobin in blood or tissue by administering a therapeutically amount of an isolated or recombinant microperoxidase are also described. Methods of determining the effectiveness of a microperoxidase for removing CO from hemoglobin are further described.
