Chemical Research in Chinese Universities ›› 2018, Vol. 34 ›› Issue (5): 758-766.doi: 10.1007/s40242-018-8237-4

• Articles • Previous Articles     Next Articles

QM/MM Investigations on the Bioluminescent Decomposition of Coelenterazine Dioxetanone in Obelin

YUE Ling   

  1. Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter, Ministry of Education, School of Sciences, Xi'an Jiaotong University, Xi'an 710049, P. R. China
  • Received:2018-07-23 Revised:2018-08-07 Online:2018-10-01 Published:2018-08-23
  • Contact: YUE Ling,Email:heartstar@mail.xjtu.edu.cn E-mail:heartstar@mail.xjtu.edu.cn
  • Supported by:
    Supported by the National Natural Science Foundation of China(No.21503156) and the China Postdoctoral Science Foundation(No.2015M572544).

Abstract: The bioluminescent mechanism of colenterazine dioxetanone(CZD) in the photoprotein of Obelia(obelin) was investigated by the combined quantum and molecular mechanics(QM/MM) method at TD-DFT level, which involved the real protein environment in decomposition of 1,2-dioxetanones. The anionic decomposition of CZD in (CZD+H2O)- model can go through a charge transfer(CT) catalyzed asynchronous-concerted process, which can be elucidated by the gradual reversible CT initiated luminescence(GRCTIL) mechanism. The neutral CZD in (CZDH+H2O) decomposes through an uncatalyzed non-CT biradical process. The anionic decomposition catalyzed by CT, in which the S0/S1 surface "double crossing" hence has ability to provide high quantum yield of singlet chemiexcitation is thus more possible in bioluminescence of photoprotein.

Key words: 1,2-Dioxetanone, Bioluminescence, Coelenterazine, Photoprotein, Quantum and molecular mechanics