Article

Crystal Structures of the Luciferase and Green Fluorescent Protein from Renilla reniformis

Molecular Imaging Program at Stanford, Department of Radiology and Bio-X Program, The James H. Clark Center, Stanford University School of Medicine, 318 Campus Drive, Clark E150, Stanford, CA 94305-5427, USA.
Journal of Molecular Biology (Impact Factor: 3.96). 01/2008; 374(4):1017-28. DOI: 10.1016/j.jmb.2007.09.078
Source: PubMed

ABSTRACT Due to its ability to emit light, the luciferase from Renilla reniformis (RLuc) is widely employed in molecular biology as a reporter gene in cell culture experiments and small animal imaging. To accomplish this bioluminescence, the 37-kDa enzyme catalyzes the degradation of its substrate coelenterazine in the presence of molecular oxygen, resulting in the product coelenteramide, carbon dioxide, and the desired photon of light. We successfully crystallized a stabilized variant of this important protein (RLuc8) and herein present the first structures for any coelenterazine-using luciferase. These structures are based on high-resolution data measured to 1.4 A and demonstrate a classic alpha/beta-hydrolase fold. We also present data of a coelenteramide-bound luciferase and reason that this structure represents a secondary conformational form following shift of the product out of the primary active site. During the course of this work, the structure of the luciferase's accessory green fluorescent protein (RrGFP) was also determined and shown to be highly similar to that of Aequorea victoria GFP.

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