Coelenterazine and its analogs are luminescent enzyme substrates for apoaequorin and Renilla luciferase.

Coelenterazine and its analogs are luminescent enzyme substrates for apoaequorin and Renilla luciferase. Apoaequorin is used as a calcium indicator whereas Renilla luciferase is commonly used as a reporter of transcription regulation. Coelenterazine binds to apoaequorin to form aequorin which emits light upon binding to calcium. Aequorin can be used to measure a broad concentration range of calcium from ~0.1 uM to >100 uM. Renilla luciferase has been widely used as a reporter protein and as a bioluminescence donor in bioluminescence resonance energy transfer (BRET) to study protein-protein interactions. Other uses of coelenterazine include chemiluminescent detection of superoxide anion and peroxynitrite in cells or tissues.

Can’t decide which coelenterazine analog to use? Try the Coelenterazine Sampler Kit (catalog no. 89138-348). The kit includes 25 ug each of nine coelenterazine analogs including native, cp, f, fcp, h, hcp, i, ip and n.

There are over a dozen of coelenterazine analogs that have been synthesized, many of which are now commercially available from Biotium. These coelenterazine analogs have different properties in terms of emission wavelength, cell membrane permeability and quantum efficiency.

Biotium offers coelenterazine 400a (also known as DeepBlue C™) (catalog no. 89138-350) which serves as a substrate for Renilla luciferase (Rluc) and generates an emission peak centered around 400 nm. It is the preferred Renilla luciferase substrate for BRET studies because it has minimal interference with the emission of the GFP acceptor.
Also, see Biotium's water soluble Aquaphile™ Coelenterazines, sold as coelenterazine native (catalog no. 89411-152) or coelenterzine h analog (catalog no. 89411-156). These formulations readily dissolve in water or buffer for in vivo use.
Lastly, Biotium offers methyl coelenterazine (coelenterazine, 2-methyl analog) (catalog no. 89138-344) which has been reported to be a superior antioxidant for cells against reactive oxygen species (ROS) such as singlet oxygen and superoxide anion. The coelenterazine derivative is membrane-permeant, non-toxic and highly reactive toward ROS.