Antarctic worms’ antifreeze “superpowers” come from their microbiome

In the frigid waters of the Antarctic Ocean, only the hardiest animals survive. Some layer up with blubber to keep warm. Others produce natural cryoprotectants, either antifreeze proteins or smaller molecules, to prevent ice nucleation in their cells. Now, researchers have discovered three marine worm species that take a different approach: outsourcing the production of antifreeze proteins to their microbiome (Sci. Adv. 2024, DOI: 10.1126/sciadv.adk9117).

The team set out on a boat to collect wild polychaetes—marine worms—from the sediment beneath Antarctica’s Terra Nova Bay, writes lead researcher Cinzia Corinaldesi, a marine ecologist at the Polytechnic University of Marche, in an email. When the team compared the proteomes of the collected worms to the proteomes of the worms’ microbiomes, she says they were thrilled to discover that “the cryoprotective proteins in the polychaetes were not produced by the worms, but by the bacteria.” It’s as if the worms’ microbiomes give them survival “superpowers.”

“The idea that the microbiome of an organism can confer properties the organism needs to survive is a super cool avenue of research,” says Byron Adams, a biologist at Brigham Young University who studies how Antarctic nematodes on land survive brutal conditions. This work is compelling, he says. Next, Adams hopes the researchers drill down into the mechanism and “follow the genes in the bacteria through their expression and then usage by the worm.”