Re: [DIYbio] modified GFP -> pr-coelenterazine peptide

 The luciferin used by A. victoria and Renilla is called coelenterazine, and it kinda looks like three amino acids connected together in a weird way.

It turns out that GFP has to go through some post-translational modifications before it becomes active, including a cyclization reaction in three of the amino acids that make up its chromophore.

The patent that Mega pointed out in the other thread claims that by making just a single amino acid change to GFP, that maturation process will actually produce coelenterazine!

That's why he was asking "So why the wild-type GFP doesn't produce the luciferin?" I suspect that Renilla (and A. victoria) either carry a second modified GFP gene which is used to produce coelenterazine, or they may have some protein-modifying enzyme that can produce the coelenterazine precursor from GFP. They presumably also have enzymes to recycle the oxidized coelenterazine, so you don't have to sacrifice a whole protein for every photon you want to produce.