Scientists begin to release the chemistry behind the magic light
Predators walking on a worm colony can become thinner. When these sea creatures are endangered, they emit a sticky slime that can turn blue for days (SN: 7/28/14).
This type of light, produced by animals, bacteria or algae, usually disappears in an instant (SN: 6/12/16). But by sliding worms out of the Chaetopterus tube, “we easily have 16 hours and sometimes 72 hours of light,” said Evelien De Meulenaere, a biochemist at the Scripps Institution of Oceanography in La Jolla, California. Light can help make it glow by triggering chemical reactions that keep it glowing.
Creating and maintaining such bioluminescence takes vigor. However, the energy source of mucus is a mystery, as it shines outside the body and does not draw energy from the worms within. To unlock its secrets, scientists are studying the complex chemistry of glue.
De Meulenaere and his colleagues noticed a spike in the slimy light as they exposed the slime to blue light. “It’s the strangest thing,” she said. “The mud itself produces a blue light. Does it make itself?”
To find out, the researchers separated molecules in mucus based on their size and other properties to identify proteins, sugars, and metals. This process of snorting the mucus recipe revealed that iron can help maintain a permanent shine. Mucus contains ferritin, a protein that stores iron and releases iron electrons charged with electricity or ions. These ions can produce mud that emits flashes of blue light, the team found.
Ferritin itself appears to respond to blue light with the help of another molecule that absorbs blue light by releasing ions more quickly, De Meulenaere and his team found. This indicates that the light from the mud can help create more light to maintain the lighting. The team planned to present the results of Experimental Biology 2020 in early April, but the meeting was canceled due to the COVID-19 pandemic.
The goosebumps glow was first studied in the 1960s and then largely forgotten, says Warren Francis, a biologist at the University of Southern Denmark in Odense, who was not involved in the study. The new research sheds light on the repeated luster of the mud, but the data still does not give a clear picture of the role of blue light and ferritin in glow chemistry, he said.
“When we understand how it works, we get a great clue as to how animals function in their own world,” Francis said. And that will help people as well. The bioluminescence of jellyfish and fireflies has provided powerful tools that biologists can use to study how cells work. “There can be a lot of uses,” he says.
Maybe one day, according to the study’s authors, scientists could use snot secrets to create a lasting light that continues to shine.