Luciferase from Renilla reniformis (RLuc) catalyzes the degradation of coelenterazine in the presence of molecular oxygen, resulting in the product coelenteramide, carbon dioxide, and the desired photon of light (EC 1.13.12.5). This enzyme belongs to the Haloalkane dehalogenase family II with a different catalytic function (EC 3.8.1.5) Reconstruction of an ancestral enzyme shows it has both hydrolase and monooxygenase activities ( Chaloupkova et al.). This luciferase produces light with a wavelength of 480 nm. In presence of a green fluorescence protein (GFP) it produces a green fluorescence at 509 nm. It is different of most other luciferases which are not alpha Beta hydrolases