Hemocyanin

PDB ID: 1NOL

Blue Blood? That a Hemo-SIGN-anin that you have Hemocyanin in your blood! Hemocyanin is a protein that is found in molluscs, such as snails, octopi, and crabs, and it carries oxygen just as hemoglobin does in our bodies. Similar to hemoglobin, a central metal atom binds oxygen, but in hemocyanin, this central atom is copper, which is represented in my model with copper wire and 2 blue ball structures. The blue beads of the various creatures represent the hemocyanin circulating in their blood. They are floating to represent the free floating quality of this protein. Oxygenation causes a color change between the colorless Cu(I) deoxygenated form and the blue Cu(II) oxygenated form, making the blood of the creatures appear blue!