Abstract
The photoprotein aequorin isolated from the jellyfish Aequorea victoria emits blue light in the presence of Ca2+ with a high quantum yield. Aequorin consists of apoaequorin (apoprotein), coelenterazine, and molecular oxygen. Coelenterazine also has a chemiluminescent reactivity with oxygen. In vivo, the excited energy generated by aequorin is transferred to a green fluorescent protein (GFP), which emits green light after energy transfer. The molecular processes in the jellyfish bioluminescence have been studied for designing a highly efficient luminescent compound and for establishing the supramolecular interaction between coelenterazine and apoaequorin as well as the interaction between aequorin and GFP. This review describes the chemiluminescent reaction mechanism of coelenterazine, the supramolecular structure and the bioluminescent character of aequorin investigated by the use of chemically modified coelenterazines and apoaequorin mutants, and the character of GFP.
