Biosensing firefly luciferin synthesis in bacteria reveals a cysteine-dependent quinone detoxification route in Coleoptera

Author(s)

de Souza, Daniel Rangel ; Silva, Jaqueline Rodrigues ; Moreira, Ariele ; Viviani, Vadim R.

• Document type: Journal article
• Source: SCIENTIFIC REPORTS; v. 12, n. 1, p. 12-pg., 2022-08-31.

Abstract

Luciferin biosynthetic origin and alternative biological functions during the evolution of beetles remain unknown. We have set up a bioluminescent sensing method for luciferin synthesis from cysteine and benzoquinone using E. coli and Pichia pastoris expressing the bright Amydetes vivianii firefly and P. termitilluminans click beetle luciferases. In the presence of d-cysteine and benzoquinone, intense bioluminescence is quickly produced, indicating the expected formation of d-luciferin. Starting with l-cysteine and benzoquinone, the bioluminescence is weaker and delayed, indicating that bacteria produce l-luciferin, and then racemize it to d-luciferin in the presence of endogenous esterases, CoA and luciferase. In bacteria the p-benzoquinone toxicity (I-C50 similar to 25 mu M) is considerably reduced in the presence of cysteine, maintaining cell viability at 3.6 mM p-benzoquinone concomitantly with the formation of luciferin. Transcriptional analysis showed the presence of gene products involved with the sclerotization/tanning in the photogenic tissues, suggesting a possible link between these pathways and bioluminescence. The lack of two enzymes involved with the last steps of these pathways, indicate the possible accumulation of toxic quinone intermediates in the lanterns. These results and the abundance of cysteine producing enzymes suggest that luciferin first appeared as a detoxification byproduct of cysteine reaction with accumulated toxic quinone intermediates during the evolution of sclerotization/tanning in Coleoptera. (AU)

• FAPESP's process: 18/07925-3 - Transcriptional comparison of the integument of bioluminescent and non-bioluminescent coleopteran larvae during ecdysis; isolation, expression and characterization of coumarate-ligases and laccases; and relation between pigmentation and bioluminescence
• Grantee: Jaqueline Rodrigues da Silva
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 18/17855-2 - Cloning, expression and characterization of Phengodidae luciferases and proteins of bioluminescent system: structural, functional and evolutive aspects
• Grantee: Daniel Rangel de Souza
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)