RICHLAND, Wash. -- Tiny electrical wires protrude from some bacteria and contribute to rock and dirt formation. Researchers studying the protein that makes up one such wire have determined the protein's structure. The finding is important to such diverse fields as producing energy, recycling Earth's carbon and miniaturizing computers.
"This is the first atomic resolution structure of this protein from an electrically conductive bacterial species, and it sets the foundation for understanding how these nanowires work," said structural biologist Patrick Reardon of the Department of Energy's Pacific Northwest National Laboratory. Reardon is the 2012 William R. Wiley Distinguished Postdoctoral Fellow at EMSL, the DOE's Environmental Molecular Sciences Laboratory at PNNL.
With the help of related structures on disease-causing bacteria, the researchers show that the protein's shape and form suggest possible ways for the bacteria to shuttle electrons along the nanowire. The results are reported in October in the Journal of Biological Chemistry.
"How to get electrons from the inside of bacteria to the outside is important for many different things, such as bacterial fuel cells, how carbon cycles through the environment and how to make new nanomaterials for applications like biocomputers," said Reardon.
Many bacterial species wave fingerlike projections along their bodies. The bacteria use these fingers, called pili, to adhere to surfaces or weave into films or recognize objects in the environment. A group of related bacteria makes these bendy, stretchy structures out of a protein called pilin, and an even smaller group uses these structures like electrical wires.
Researchers and engineers would like to take advantage of this wiring. Bacteria produce electrons while respiring and use the wires to run electrons out of their little bacterial bodies. Normally the electrons build up or
|Contact: Mary Beckman|
DOE/Pacific Northwest National Laboratory