Geobacter are a remarkeable group of bacteria.
I first read about them in a BBC news article about bacteria that were able to remove Uranium for contaminated water (click here for the article). But after some research they seem even more amazing as …
… they can also be used to clean up spilt petroleum.
What makes them remarkable is that they produce a series of nanowire that connects them to the substance being reacted. They substance is broken down outside the cell at the ends of the nanowires, thus the cell itself does not get contaminated.
Breaking down the substance produces electrons which has led scientists to speculate it could be used to act as a battery.
A longer and more detailed article on Geobacter can be found here.