Firefly oxyluciferin is the product of firefly bioluminescence and is formed directly in an excited state, due to the luciferase enzyme catalyzed adenylation and oxidation reactions.1,2 Various advantageous characteristics lead to the development of various applications in areas such as biomedicine and molecular biology. Nevertheless, newer applications can be found and the efficiency of already established ones increased, if the color tuning mechanism of firefly oxyluciferin is elucidated.Our group has been trying to achieve this goal, by employing a variety of computational methodologies, which provide detailed and accurate electronic structure information. We have studied luciferase-oxyluciferin complexes of different firefly species, based on density functional theory and molecular mechanics (TD-DFT/MM).3,4Our results indicated that the color tuning was obtained by modulating electrostatic, hydrogen bonding and ?-? stacking interactions with active site molecules.More recently, a crystallographic studied demonstrated that the light-emitting conformation of luciferase is very different from what seen in previous studies, due to a C-domain ~180 degrees rotation. Given this, the objective of this communication is to the present the results related to the characterization of the firefly bioluminescence color tuning mechanism in the real light-emitting complex, by employing a TD-DFT/MM methodology.References1. L. Pinto da Silva, J.C.G. Esteves da Silva, J. Chem. Theory Comput. 2011  , 7, 809-817.2. L. Pinto da Silva, J.C.G. Esteves da Silva, ChemPhysChem 2012  , 13, 2257-2262.3. L. Pinto da Silva, J.C.G. Esteves da Silva, ChemPhysChem 2011  , 12, 3002-3008.4. L. Pinto da Silva, J.C.G. Esteves da Silva, J. Phys. Chem. B 2012  , 116, 2008-2013.5. J.A. Sundlov, D.M. Fontaine, T.L. Southworth, B.R. Branchini, A.M. Gulick, Biochemistry 2012  , 51, 6493-6495.

Firefly color tuning mechanism: A TD-DFT/MM characterization

248th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.