Understanding the complete bioluminescence cycle from a multiscale computational perspective: A review

Bioluminescence (BL) is an amazing natural phenomenon whose visible light is produced by living organisms. BL phenomenon is quite pervasive and has been observed in 17 phyla of 4 kingdoms. This fascinating natural phenomenon has unceasingly attracted people's curiosity from ancient era to today. For a very long time, we can only receive some sporadic and static information from experimental observations, the mechanism of most BL remains is unclear. How the chemical reaction of BL process is initiated? Where the energy for light emission comes from? How does the light emitter produce? What is the light emitter for a wild bioluminescent organism? How to regain luciferin for next bioluminescence when it is used up? The luciferin is utilized forthwith or stored and release for subsequent light emission? What factors affect the color and strength of a bioluminescence? How to artificially tune the bioluminescence for special application? Computational BL plays unreplaceable role in answering these mechanistic questions. In contrast with experimental BL, computational BL came very late. In the past two decades, computational BL has touched nearly all the bioluminescent systems with chemical bases via the method of multiscale simulation. In this review, the author firstly introduced the history, types and general chemical process of BL. Then, the computational scheme on BL was briefly epitomized. Using firefly BL as a paradigmatic case, the author summarized theoretical investigation on the six stages of general chemical process in a BL cycle: luciferin oxidation, peroxide thermolysis, light emission, luciferin regeneration, luciferin storage and luciferin release. At each stage, the available theoretical studies of other bioluminescent organisms are briefly introduced and compared with the firefly system. Basing on the mechanistic understanding, the author reviewed the up-to-date theoretical design on bioluminescent systems. Again, the firefly was mainly focused on, and the other possible systems were just briefly introduced. This review summarized the theoretical studies to date on BL and addressed the status, critical challenges and future prospects of computational BL.