Bacteria Power - About Bacteria Power | Power Of bacteria - Will our cars run on bacteria power one day? Mud-dwelling bacteria of the genus Geobacter release electrons as they consume organic pollutants and decaying plant and animal matter. (Humans and other organisms also produce electrons during cellular respiration, but these combine with oxygen and hydrogen atoms to form water (Chapter 15). Geobacter, on the other hand, releases its electrons directly.) By designing a simple system for catching these electrons, biologist Derek Lovley and his colleagues at the University of Massachusetts, Amherst, were able to create a battery that runs on pure bacteria power. Lovley collected polluted mud and seawater from Boston Harbor and placed them in a ﬁsh tank. He then stuck an electrode in the mud and connected it with copper wire to a second electrode in the seawater. Over time, Geobacter bacteria gathered on the mud-embedded electrode and passed electrons out their cell membranes as they ate. These electrons moved up the copper wire, producing an electric current.
|A series of Geobacter “batteries” (the tubes in the background) are powering this calculator.|
The next challenge will be to make Geobacter energy generation more efﬁcient. At present, it would take many square miles of muddy seaﬂoor to generate 60 watts, the amount of power required to run a household light-bulban unrealistic proposition. Scientists are tackling this problem now and have taken the ﬁrst step of sequencing the Geobacter genome. Studying Geobacter’s genes may just help them ﬁgure out how to get the bacteria to eat faster. In fact, it appears that Geobacter has more than 100 genes that are related to its ability to transfer electrons. If scientists are successful at manipulating these, we may soon have microbial fuel cells
that run on garbage and other organic wastes. In the meantime, Geobacter is already making itself useful running weather sensors and deep-sea mapping instruments, devices that require only 1watt of power.