Invasive zebra mussels’ unique sticky threads unraveled

Zebra mussels are among the worst invasive species in freshwater ecosystems. Using extremely sticky byssal threads they attach themselves to boats and travel the world, establishing themselves in new locations and choke out native species. Now, new research shows the structure of Dreissena byssal threads are unique among mussels and may account for their invasiveness.

Matthew Harrington, a chemist at McGill University in Montreal, has studied marine mussel adhesion proteins and their potential applications for bio-inspired materials since graduate school. It wasn’t until arriving at McGill University that he studied zebra mussels, however, ‘because we can just go to the St Lawrence River and pull them out’, he says. Across mussel species the function of byssal threads is the same but they are structurally different. Some are made of collagen and others globular proteins that arrange into helices, Harrington explains. However, Harrington immediately recognised that zebra mussels’ threads were unique. ‘It was really clear that this was neither globular nor collagen it was a completely new biochemical structure.’