Mussel wire in the operating room?
Publication in the Journal of L’UQAM
Whether prepared with white wine or cream, mussels have many followers: in Canada, they harvest more than 20,000 tonnes per year. But before landing in our supermarkets, the mussels must be debyssed, that is to say free from their byssus, this bundle of golden and rough wires which allows them to attach themselves to the rocks.
For now, the byssus is simply thrown in the garbage, which represents 200 tonnes of waste per year. Isabelle Marcotte, professor in the Department of Chemistry, and her colleague Christian Pellerin, of the University of Montreal, want to find a better use for it. The byssus has indeed exceptional properties.
“In terms of strength, rigidity and elasticity, byssus is only surpassed by spider silk,” says Isabelle Marcotte. Araneidae canvas, as we know, is a star material stronger than steel and its potential uses are multiple.
An incredible complexity
To unravel the secret of the Myssilus edulis byssus – the most widespread mussel species on the Atlantic coast – and understand its mechanical advantages, Isabelle Marcotte’s team is studying its molecular structure using nuclear magnetic resonance techniques and spectroscopy. Each thread of the byssus is made up of an interminable protein rich in collagen, whose atomic composition varies from one end to the other of the filament. The whole is incredibly complex: according to the team’s observations, certain areas of the byssus are more dynamic than others and the molecules have more freedom of movement there.
Isabelle Marcotte wants to understand how different factors – such as temperature, availability of food or the turbulence of sea currents – affect the resistance of the byssus. To do this, she collaborates with Réjean Tremblay of the Rimouski Institute of Marine Sciences (ISMER). The latter demonstrated that in autumn, when the sea is rough, the byssus can resist a pull of 40 Newtons – the equivalent of the force exerted by a bottle of bleach in suspension – while in summer, half this force is enough to tear the mollusk from its anchoring site. The purpose of this analysis: to be able to plan the harvest of byssus at the right time, so as to maximize the properties of the biomaterials that will result.
Artificial tendons and suture
It is in the operating rooms that the byssus could eventually enter. Artificial tendons, sutures or vehicles for administering drugs: there are many possibilities for this harsh growth of the mollusc, whose high protein content reduces the risk of rejection by the human body.
In the shorter term, the work of UQAM chemists is a source of hope for growers, in particular those affiliated with the Center maricole des Îles-de-la-Madeleine (MAPAQ), who are participating in the study. Currently, they are losing up to a third of the molds they produce. You should know that they are cultivated around an undersea cable to which they cling. Many of them fall to the bottom of the water.
In addition to being a significant loss to the industry, this phenomenon creates an accumulation of organic matter in the seabed, called eutrophication. Isabelle Marcotte wants to solve this problem: “By better understanding the mechanisms that influence the attachment strength of mussels, we can suggest new methods of breeding and harvesting. In addition, we can recover a fiber that is normally thrown away, which opens up a new market for breeders! ”
Who would have thought that chemists in their laboratory would one day help mold producers to make ends meet?
Sources: Actualités UQAM.