Milan, December 28 - The secret of the powerful natural glue produced by mussels has been revealed - its strength is in a 'drying' protein that removes water molecules and then adheres tenaciously to the substratum. Thanks to its properties it will be possible to develop new water resistant adhesives, biodegradable and bio-compatible, useful both in the shipping sector and in surgery for suturing wounds and repairing fractures. The discovery, published in the journal Nature Communications, was made by the Nanotechnology Institute of the National Research Council (CNR-NANOTEC) at Rende in Cosenza province, in collaboration with the university of Calabria and the Nanyang Technological University of Singapore. "This is a result of great applicative relevance, because even the most tenacious of modern synthetic adhesives are inefficient in the presence of water molecules," said Bruno Zappone, from CNR-NANOTEC. The secret was discovered studying Asian green mussels. Those molluscs produce sticky spittle drying various proteins in a well orchestrated sequence. First the mussel produces a drying protein that removes the water molecule and ties itself strongly to the substratum. On this first superficial layer a complex tissue then is constructed in which every protein has a specific function (like protection from the external environment). "An 'underwater glue' could have important applications in the shipping sector but applications in medicine would be extraordinary for instance in rebuilding damaged tissue or repairing detached retinas or integrating biomedical materials in the presence of biological liquids," Zappone said.