Bioluminescent fungi reveal pathways for advanced biotechnology and medical applications

Like fireflies and many deep-sea creatures, certain fungi can naturally emit light through bioluminescence pathways in which specialized enzymes convert chemical energy into visible light. Medical researchers have used fungal light-producing enzymes in the Fungal Bioluminescence Pathway (FBP) to visually track processes like tumor progression and inflammatory responses. New research published in The FEBS Journal provides insights that may help improve and expand such bioluminescence-based tools and applications.

One of the products of the FBP is oxyluciferin, which in fungi is subsequently degraded and recycled back into the pathway, sustaining the bioluminescent process. Previous studies have suggested a role for the caffeylpyruvate hydrolase (CPH), the last of four enzymes involved in the FBP, in breaking down oxyluciferin, but results have been inconclusive. In this latest study, investigators characterized CPH from one of the largest and brightest bioluminescent fungal species described to date, confirming that the enzyme converts oxyluciferin into caffeic and pyruvic acids. Caffeic acid can re-enter the pathway to sustain light emission, while pyruvic acid may be redirected into central metabolism to help generate cellular energy, potentially reducing the energetic cost of bioluminescence. The scientists also developed a new method to monitor CPH activity, thereby providing a useful resource for further studies on bioluminescence.

The findings could be used to develop self-sustained light-emitting systems in other organisms, with potential applications across medicine, agriculture, environmental monitoring, and biotechnology.

After eight years of work, we were finally able to demonstrate that the breakdown of fungal oxyluciferin by CPH produces caffeic acid and pyruvic acid. This finding helps explain how fungi sustain bioluminescence through metabolite recycling while potentially recovering part of the energy invested in light emission. It also provides important insights for the design of engineered cells capable of emitting brighter light in a more efficient and sustainable way."

Cassius V. Stevani, PhD, co–corresponding author, University of São Paulo, Brazil