Nontoxic, naturally produced amino acids comprise the elements of a bacteria strain newly engineered by University of Massachusetts scientists, researchers reported recently in the latest issue of Small, approaching the thinnest wires known.
Microbiologist Derek Lovley led a team to craft the bacteria
from wires made from feedstocks without using chemical processes typically
employed in nanoelectronics in an effort to find sustainable sources of
electronic materials. Lovley’s discovery may have applications for transistors
and capacitors as well as wire, such as biocompatible sensors, computer parts
and solar energy components.
The U Mass team embarked on the path toward its discovery approximately 10 years ago, working with a soil microorganism to
learn that the substance could grow electrically conductive filaments on iron
minerals contained within soil.
“As we learned more about how the microbial nanowires worked
we realized that it might be possible to improve on Nature’s design,” Lovley said. “We knew that one class of amino acids was important for the
conductivity, so we rearranged these amino acids to produce a synthetic
nanowire that we thought might be more conductive.”
The scientists used tryptophan with successful results. Not
only were they able to create a durable strain of the microorganism (Geobacter), but its conductivity proved
2000 times greater than the natural substance.
“We were blown away by this result,” Lovley said. “It’s quite an unusual protein…this may be just the beginning.”