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Why do different organisms have different luciferins and luciferases?

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time-lapse photo of fireflies — Bioluminescence Time-lapse image of fireflies in the Catskill Mountains, New York. Firefly light is a cold light, with approximately 100 percent of the energy given off as light and only a minute amount as heat. Only light in the visible spectrum is emitted.

Different organisms utilize distinct types of luciferins and luciferases because bioluminescence has evolved independently across many diverse groups of organisms.1

Rather than a single universal mechanism, bioluminescence relies on specific enzyme-substrate pairings that have developed separately in various lineages, such as bacteria, fireflies, and marine organisms. Because each type of luciferin possesses a unique chemical structure, it requires a corresponding, specific luciferase enzyme to catalyze its oxidation and produce light.23

For example, while fireflies use a complex reaction involving ATP, bioluminescent bacteria employ a different process involving the enzymatic oxidation of reduced flavin mononucleotide (FMNH2) and a long-chain aliphatic aldehyde. This diversity in chemical components reflects the independent evolutionary paths these organisms took to achieve the survival advantages provided by light production, such as mating signals, prey attraction, or defense.214