title: Structure based mechanism of the Ca(2+)-induced release of coelenterazine from the Renilla binding protein.
abstract: The crystal structure of the Ca(2+)-loaded coelenterazine-binding protein from Renilla muelleri in its apo-state has been determined at resolution 1.8 A. Although calcium binding hardly affects the compact scaffold and overall fold of the structure before calcium addition, there are easily discerned shifts in the residues that were interacting with the coelenterazine and a repositioning of helices, to expose a cavity to the external solvent. Altogether these changes offer a straightforward explanation for how following the addition of Ca(2+), the coelenterazine could escape and become available for bioluminescence on Renilla luciferase. A docking computation supports the possibility of a luciferase-binding protein complex.
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602, USA.
authors.forename: Galina A
authors.initials: GA
authors.lastname: Stepanyuk
authors.forename: Zhi-Jie
authors.initials: ZJ
authors.lastname: Liu
authors.forename: Eugene S
authors.initials: ES
authors.lastname: Vysotski
authors.forename: John
authors.initials: J
authors.lastname: Lee
authors.forename: John P
authors.initials: JP
authors.lastname: Rose
authors.forename: Bi-Cheng
authors.initials: BC
authors.lastname: Wang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D002118:Calcium / Q000737:chemistry* / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000737:chemistry* / Q000378:metabolism; D018360:Crystallography, X-Ray; D007093:Imidazoles / Q000737:chemistry* / Q000378:metabolism; D049410:Luciferases, Renilla / Q000737:chemistry* / Q000378:metabolism; D049408:Luminescent Agents / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D011719:Pyrazines / Q000737:chemistry* / Q000378:metabolism; D048790:Renilla / Q000201:enzymology / Q000378:metabolism; D013050:Spectrometry, Fluorescence; D013329:Structure-Activity Relationship; D013379:Substrate Specificity
chemical_list: D002135:Calcium-Binding Proteins; D007093:Imidazoles; D049408:Luminescent Agents; D011719:Pyrazines; C519338:luciferin-binding protein, Renilla; C017144:coelenterazine; D049410:Luciferases, Renilla; D002118:Calcium