Bacterial nanowires

Kat:: Now I saw a paper this month in Nature which is from a team in Denmark in the US and this is electric bacteria. I absolutely love this. It turns out that there's little bacteria, tiny, tiny bacteria, which you think are solitary beings and they gang up together and make tiny electrical wires. Why are they doing this?

Nell:: So, these are bacteria that are living in that really kind of stinky horrible mud you get if you have a go at sort of walking by the seaside. You're in your wellies and you stump into the mud and it smells like farts, and it's just utterly gross. But the bacteria living in there and part of the reason why the mud smells so foul is because there's no oxygen in there to help break down all the kind of gunk and stuff. The bacteria have a problem with this too. If they're living really deep down in the mud, they can't get the oxygen which is up at the surface. So, they are teaming up. They're forming these little filaments right through the mud, so that the bacteria at the top can put electrons onto oxygen and the bacteria at the bottom are taking electrons off sulphides in the mud. So, it's like a kind of team effort to breath and eat at the same time, but doing it altogether.

Kat:: It's really fascinating that you think of bacteria, just as being solitary things, but actually, there's quite a lot of single-celled organisms that gang up together and do things like this and this is really interesting example. I wonder if we you could make living microchips or living electrical devices with these bacteria.

Nell:: There's always been this idea that multicellular organisms might have evolved in this way perhaps. So you start off with your one bacteria. They start teaming up together and when it gets to the point that they can't work without each other any more, essentially, you got a whole new organism. So, it's quite interesting to see something that's sort of in between the two extremes if you like.