Luminescent worms - ideas for sustainable light sources

New research published in FASEB suggests that Chaetopterus marine worm mucus could become a long-term light source for future technology. 

Bioluminescence has long been observed in many organisms such as fireflies, algae, jellyfish or tubeworms. Some use light as a defense mechanism to surprise or distract enemies; others turn it into a means to disguise or attract a mate.

Paper-tube worms glow (right) when they feel threatened. (Photo: IFL Science).

In most cases, the phenomenon usually takes a while, such as the plankton in the ocean only flashes when the surface of the water is stirred at night. However, in paper-tube worms (Chaetopterus) , the mucus they secrete has a slow burning effect, producing long lasting blue light.

"The light generated by Chaetopterus does not appear as a flash, but lasts very long," said Dr. Evelien De Meulenaere, a researcher at the Dimitri Deheyn Laboratory of the Scripps Institution of Oceanography in the United States. "Understanding the mechanics of this process could be the key to designing light-emitting diodes (lightsticks) that work over the days and are environmentally friendly, used to illuminate gardens or streets."

Detailed analysis of the worm's mucus revealed it contained an iron storage protein called ferritin. When added in large quantities, ferritin can increase the brightness of secretions. Scientists describe the protein as a battery that stores energy for green light.

"Light sources based on this mechanism can be activated remotely using blue light to initiate and amplify the process," De Meulenaere explained. "Once we understand exactly how natural systems produce light, we can develop sustainable light sources that are both biodegradable and rechargeable."

The scientists believe the research could be used as a "glow card" for proteins or cells in experiments. The current choice of fluorescent lighting has the disadvantage of being too light-emitting time; while the mucus of Chaetopterus can brighten for days. 

In addition to being a self-sustaining light source, the team also hopes that the worm's slime could be used to diagnose iron toxicity or deficiency due to the sensitivity of ferritin. 

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