today includes two stories related to the humble mussel. The first has to do with the excellent binding properties of the fibres that mussels use to stick to every conceivable surface (including each other), while the second discusses their continued survival in an ocean environment that continues to warm up; not unlike the chilli mussel soup I found myself craving after researching this one. Both articles were first encountered on Eurekalert. As usual, the transcript follows the jump.
Transcript — ‘Stretching Our Muscles’
Hello and welcome to another episode of the Tooth Soup Science Pod. My name is Phill English and today I bring you two stories regarding the plight and potentially life-saving science of mussels. To the latter first, and mussels have long been known for their ability to stick to stuff. If you’re a mussel, your To-Do list consists of two activities: number one is feeding on plankton through your siphon and number two is continuing to stick to whatever wave-washed rock you’re currently humping. Every now and again you might release some sperm if you’re a male mussel or accept some (through the same siphon used for feeding) if you’re a female, but besides that, it’s all about food and fastening.
Now, you may be like me and be labouring under the impression that mussels are pretty much only good for an additive to a nice spaghetti or featuring in a big old bowl of chilli sauce. But thanks to some research from the group of Herbert Waite, a biologist at the University of California, mussels have been implicated in the development of a water-resistant bio-glue.
So why mussels? As previously mentioned, mussels have evolved the ability to stick to surfaces that are often flooded with water. They do this by searching with their ‘foot’—a tongue-like organ they can use to pull themselves along—until they find a crevice, usually on a rock. They can then use their foot to create a vaccuum on the surface of the rock, and pump in ‘byssus’; a liquid soup of proteins that hardens as an adhesive and secures the mussel to the surface. I was also surprised to learn that mussels use this byssus adhesive as a defensive weapon, anchoring predatory sea snails to rocks so that they can’t move and end up starving to death. Turns out mussels are pretty badass! As a sidenote to their badassery, the threads of byssus are also referred to as ‘sea silk’ and can be spun into cloth which is finer than ordinary silk and also apparently both very light and very warm.
Anyway, as it turns out, it’s the proteins in byssus that got the attention of the researchers. They synthesised a form of an amino acid that was found in the byssus proteins and attached it to a thread-like polymer, resulting in a compound that could set rapidly and stick to wet and salty surfaces. If that sounds like it might be useful in surgery, then you’d be right. The researchers have tested the mussel-inspired compound and found that it works rather well when applied to incisions made in arteries, but also when healing holes in fetal membranes. This last has encouraging implications in the pre-natal surgery to treat spina bifida.
Unfortunately, this technology may be in hot water before it has a chance to be developed properly. Another mussel-related story popped up while I was researching for the previous one that has dire consequences for mussel survival in a warming climate. Emily Carrington, a biologist at the University of Washington, has shown that in warmer water, the byssus that attaches mussels so securely to rocks becomes a lot weaker. In fact, a rise of just 7 degrees Celcius can cause threads formed to be 60% weaker. Now, seven degrees is quite a rise, and I’m not sure if it’s a linear relationship between temperature and weakness, but if so even a few degree rise as is expected due to climate change could mean a lot more disengaged mussels floating around the ocean. Mussels have been described as a keystone of the habitat they inhabit, and so many other species could be threatened by their detachment. For the moment, biologists are talking to commercial and preservation parties to try and help them to breed resistent traits and reserve locations that are less prone to temperature shifts as future habitats for mussels.
Anyway, that’s it for now, I’ll be back next week with some more new and exciting science research. Until next time.