Definition for Photoprotein
From Biology Forums Dictionary
Photoprotein refers to broadly to a type of protein from bioluminescent organisms. The term was first used to describe the unusual chemistry of the Chaetopterus luminescent system. This was meant to distinguish them from other light-producing proteins because these do not exhibit a luciferin-luciferase reaction, that is, a normal enzyme-substrate reaction. That is to say that they do not display typical enzyme kinetics as seen in luciferases.