Myoglobin
Myoglobin is a protein that is able to bind oxygen. Myoglobin, which is similar to haemoglobin, is the main oxygen-carrying pigment of muscle tissues.[1] Like haemoglobin, it has a porphyrin ring with an iron atom at its centre. It is in the muscle tissue of most mammals. Seals and other marine mammals have more myoglobin in their muscles than land animals.
In humans, increased level of myoglobin in the serum of the blood can be an indication of myocardial infarction. Other factors for a higher level can be damage to the muscles, epileptic seizures, polytrauma. If the value is much too high, this can lead to kidney failure.
Myoglobin belongs to the globin superfamily of proteins, and as with other globins, consists of eight alpha helices connected by loops. Myoglobin has 153 amino acids.[2]
Myoglobin Media
A picket-fence porphyrin complex of Fe, with axial coordination sites occupied by methylimidazole (green) and dioxygen. The R groups flank the O2-binding site.
Molecular orbital description of Fe-O2 interaction in myoglobin.
This is an image of an oxygenated myoglobin molecule. The image shows the structural change when oxygen is bound to the iron atom of the heme prosthetic group. The oxygen atoms are colored in green, the iron atom is colored in red, and the heme group is colored in blue.
References
- ↑ Ordway G.A. & Garry D.J. (2004). "Myoglobin: an essential hemoprotein in striated muscle". J. Exp. Biol. 207 (Pt 20): 3441–6. doi:10.1242/jeb.01172. PMID 15339940. S2CID 26237923.
- ↑ Universal protein resource accession number P02144. [UniProt is the Universal Protein resource, a central repository of protein data]
