Brazilian Bioluminescent Beetles: Reflections on Catching Glimpses of Light in the Atlantic Forest and Cerrado

Abstract

Bioluminescence - visible and cold light emission by living organisms - is a worldwide phenomenon, reported in terrestrial and marine environments since ancient times. Light emission from microorganisms, fungi, plants and animals may have arisen as an evolutionary response against oxygen toxicity and was appropriated for sexual attraction, predation, aposematism, and camouflage. Light emission results from the oxidation of a substrate, luciferin, by molecular oxygen, catalyzed by a luciferase, producing oxyluciferin in the excited singlet state, which decays to the ground state by fluorescence emission. Brazilian Atlantic forests and Cerrados are rich in luminescent beetles, which produce the same luciferin but slightly mutated luciferases, which result in distinct color emissions from green to red depending on the species. This review focuses on chemical and biological aspects of Brazilian luminescent beetles (Coleoptera) belonging to the Lampyridae (fireflies), Elateridae (click-beetles), and Phengodidae (railroad-worms) families. The ATP-dependent mechanism of bioluminescence, the role of luciferase tuning the color of light emission, the "luminous termite mounds" in Central Brazil, the cooperative roles of luciferase and superoxide dismutase against oxygen toxicity, and the hypothesis on the evolutionary origin of luciferases are highlighted. Finally, we point out analytical uses of beetle bioluminescence for biological, clinical, environmental, and industrial samples.

Photoactivatable Red Chemiluminescent AIEgen Probe for In Vitro/Vivo Imaging Assay of Hydrazine

“…Furthermore, MALDI-TOF analysis of the reaction product obtained from the abovementioned mixture solution only showed the peak of ACLD (Figure S23, Supporting Information), further suggesting that ACL can be completely converted into ACLD due to the 1 O 2 generated by the AIEgen photosensitizer of TEPDC upon irradiation. Therefore, based on the abovementioned results and referring to the mechanism of luciferin, , we assume that the ACL activation strategy is dependent on 1 O 2 generation (Figure S26, Supporting Information).…”

Firefly genomes illuminate parallel origins of bioluminescence in beetles

“…Like fireflies, elaterid larvae often produce light, with the glowing termite mounds of Brazil that contain the predatory larvae of Pyrearinus termitilluminans being a striking example ( Costa and Vanin, 2010 ). A description of the anatomy of the larval light organ of Pyrophorus is provided by ( Harvey, 1952 ), and a more modern photograph of the larval light organ is provided by ( Bechara and Stevani, 2018 ). Like other bioluminescent elaterid larvae, I. luminosus larvae produce a diffuse light from their prothorax, however they are only luminous when disturbed ( Wolcott, 1948 ).…”

Intrinsic fluorescence from firefly oxyluciferin monoanions isolated in vacuo

“…Other insects emit light with maxima above 600 nm 6,9,10 so in those cases interactions within the luciferase cavity would have to provide a redshift regardless of which tautomeric form is the emitter, a conclusion that is difficult to reach based solely on solution-phase spectra as the solvent-ion interactions tune the color. One example is red cephalic luciferases of Phrixothrix heydeni that emit maximally at ≈628 nm, 9 which requires redshifting interactions in the protein pocket to account for a shift of almost 30 nm in the case of the keto form. One such interaction could be a positive charge near to the ketone C(O), which would stabilize S 1 more than S 0 (opposite to the effect of attachment of betaine to the phenolate oxygen 21 ).…”

“…[1][2][3][4][5][6] These insects emit light of different colors, ranging from green to red, with significant variations even between species of the same insect. [6][7][8][9][10] In all cases, luciferase, a light-emitting enzyme, catalyzes the oxidation of a luciferin substrate to oxyluciferin in a process involving molecular oxygen and ATP, the latter supplying the chemical energy to form oxyluciferin in an electronically excited state. Radiative decay to the ground state occurs with a high quantum efficiency, 11 which has been exploited in imaging applications within molecular and cell biology.…”