Researchers decipher composition of limpet adhesive
The marine fauna has already served as a model for numerous adhesives. However, synthetically produced variants have so far usually not come close to the biological originals. Now, a team of researchers has succeeded in completely cataloging the essential proteins and carbohydrates of the special limpet adhesive.
For more than a century, scientists have been asking the question: How does the common limpet (Patella vulgata) manage to cling rock-solidly to seashores and move around – still attached – to feed when needed? Until now, a sucking action or contraction of the snail’s muscular foot has often been suspected.
A team of researchers has now succeeded in demonstrating that a special pedal mucus allows the limpet to switch between permanent and temporary adhesion – depending on the tide or danger situation. To this end, the team led by Victor Kang (University of Cambridge) and Birgit Lengerer (University of Innsbruck) has for the first time carried out a detailed characterisation of the bio-adhesive.
Components of the limpet adhesive catalogued for the first time
Like other hydrogels, limpet pedal mucus is 90 to 95 percent water. Proteins, carbohydrates and inorganic material make up the rest. But each hydrogel is a complex system in its own right, and its function depends on the interaction of its components. To better understand the limpet’s bio-adhesive, scientists have cataloged 171 protein sequences and specific carbohydrates from it.
Although the scientists have not yet been able to identify the crucial molecular differences that lead to the switch between temporary and permanent adhesion, they suspect that the flexibility of the adhesive is linked to special enzymes that can degrade proteins. In addition, special carbohydrates are thought to enable the limpet to detach when necessary and move around on the otherwise solid mucus.
Kang, Victor; Lengerer, Birgit; Wattiez, Ruddy und Flammang, Patrich: Molecular insights into the powerful mucus-based adhesion of limpets (Patella vulgata L.), 2020.
