1. The role of CO 2 detachment in fungal bioluminescence: thermally vs. excited state induced pathways
- Author
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Marco Marazzi, Isabelle Navizet, Cristina García-Iriepa, Laboratoire de Modélisation et Simulation Multi Echelle (MSME), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Université Paris-Est Marne-la-Vallée (UPEM), University of Alcalá / Department of Analytical Chemistry, Physical-Chemistry and Chemical Engineering, Universidad de Alcalá - University of Alcalá (UAH), Chemical Research Institute 'Andrés M. del Río' (IQAR),Universidad de Alcalá, Laboratoire Modélisation et Simulation Multi-Echelle (MSME), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel, and Université Paris-Est Marne-la-Vallée (UPEM)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
010304 chemical physics ,Chemistry ,General Physics and Astronomy ,010402 general chemistry ,Photochemistry ,01 natural sciences ,Quantum chemistry ,0104 chemical sciences ,[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry ,Excited state ,0103 physical sciences ,Molecular mechanism ,Bioluminescence ,Physical and Theoretical Chemistry ,Luminescence ,ComputingMilieux_MISCELLANEOUS - Abstract
Different fungi lineages are known to emit light on Earth, mainly in tropical climates. Although the preparation of bioluminescent cell-free extracts allowed one to characterize the enzymatic requirements, the molecular mechanism underlying luminescence is still largely unknown and is based on the experimental putative assumption that a high-energy intermediate should be formed by reaction with O2 and formation of an endoperoxide. Here, we aim at determining, through state-of-the-art multiconfigurational quantum chemistry, the full mechanistic landscape leading from the endoperoxide to the emitting species, envisaging different possible pathways and proposing their viability. Especially, thermal CO2 detachment followed by excited-state peroxide opening (thermal-chemiluminescence) can compete with a parallel pathway, i.e., first excited-state endoperoxide opening, followed by CO2 detachment on the same excited-state (excited state-chemiluminescence). Clear differences in the energy supplies, as well as the possibility to directly populate the emitting species from the intersection seam between ground and excited states, land credence to a kinetically efficient thermal-chemiluminescent pathway, establishing for the first time a detailed description of fungal bioluminescence.
- Published
- 2020