Hemocyanins

**Definition:** Metalloproteins that function as oxygen transport proteins in the HEMOLYMPH of MOLLUSKS and ARTHROPODS. They are characterized by two copper atoms, coordinated with HISTIDINE residues, that reversibly bind a single oxygen molecule; they do not contain HEME groups.

**Tree numbers:** - D12.776.093.375 - D12.776.556.462 - D23.767.482

**Synonyms:** - Hemocyanin