2 Minutes with Alisdair Boraston
Ocotber 23, 2012
Understanding how proteins recognize and break down carbohydrates may seem far removed from filling a car's gas tank or finding a successful treatment for pneumonia. But, for those trying to convert carbohydrate-based biomass to produce biofuels or seeking solutions to antibiotic resistance, deciphering these interactions is crucial to success.
Biochemist Alisdair Boraston has generated numerous insights into the interactions between carbohydrates, proteins and enzymes, achievements that have earned him a 2012 E.W.R. Steacie Memorial Fellowship from NSERC.
The overall theme of my lab is structural glycobiology and that actually involves a lot of areas of research. We study sugars and we study what sugars do in nature and we study proteins that interact with sugars and modify them.
We're not just interested in the proteins and sugars just as kind of these ephemeral entities. We're actually interested in them at the atomic level, so the structural level, three dimensional structures. So we're interested in looking at how exactly proteins interact with the modified sugars by solving the structures of these proteins in complex with sugars. And then we can actually see.
It's like getting a snapshot of a car engine and being able to look at it and say, wow! that's how the thing actually works. For the natural science side is basically where I started out in science, it's an extension of it and where I started out was studying a class of enzymes called cellulases and these are enzymes that break down the cellulose in plant cell walls.
And they're all the rage because of cellulosic ethanol. I studied these for many years and then what we ended up transitioning into was a kind of a parallel system from the oceans and that's seaweed. One of the long-term objectives is being able to take that seaweed biomass and convert it into ethanol.
It's the same idea as the terrestrial plants, taking them and turning them into bioethanol but just using the seaweed which is actually there are some complexities to it but overall it's an easier problem we believe. It's going to be more successful in the end I think.
The reason it's easier is the sugars that are in there, the polysaccharides, you know the polymerized carbohydrates, they're very highly hydrated so there's lots of water in there. They're easy to get enzymes in, easy to break them apart. And so, what we do when we make ethanol from these things is you take the big polysaccharide, you break it down into little pieces and then you use another microbe, often that's a yeast like you use in beer and wine, to ferment those sugars into ethanol.
The problem with the terrestrial plant cell walls is the same property of the cellulose that makes the plant stand up is what is the big problem, that is they're crystals of cellulose. It's a solid, hard material and it's really hard to turn that into small sugars, really hard. But we think that the properties of the seaweed polysaccharides, these hydrated properties, are going to make it easier for us to convert them into these fermentable sugars.