Geobacter…Perhaps one of the best examples of the connection between the biosphere (life) and the lithosphere (rocks). For all those “Zen masters” that philosophize on the connection between “life” and “dust”, look to Geobacter!
First isolated from the Potomac River in the mid 1980’s, but since then Geobacter has been detected in various environments. So why is it such a fascinating microbe?
Imagine this: To produce energy, we humans eat food (organic matter) and breathe oxygen (aerobic respiration). The chain that links these processes is the electron. If that link is broken (the flow of electrons is stopped!) we do not produce energy and die! Well Geobacter had other ideas!
Geobacter is an old soul, from the days when there was little to no oxygen on our wonderful planet (couple billion years ago). Yet, life was around and it thrived. The first part was the same, “organic matter” was still a food option, but there was none to little oxygen. So what do you breathe to keep the electrons moving and stay alive? Geobacter evolved to “breath” iron containing rocks. Well maybe not really “breath” as you or I would, but a process to keep the electrons moving to a final destination, instead of oxygen, rocks! So how does Geobacter do this? They produce long “wires” that find and attach to iron containing rocks, and the electrons flow to the rocks just like electricity flows through the wires in your house!
So who needs oxygen when you have wires for arms…not Geobacter!
For more information on this microbe visit…. http://www.geobacter.org/