AMHERST, Mass. When researchers at the University of Massachusetts Amherst led by microbiologist Derek Lovley discovered that the bacterium Geobacter sulfurreducens conducts electricity very effectively along metallic-like "microbial nanowires," they found physicists quite comfortable with the idea of such a novel biological electron transfer mechanism, but not biologists.
"For biologists, Geobacter's behavior represents a paradigm shift. It goes against all that we are taught about biological electron transfer, which usually involves electrons hopping from one molecule to another," Lovley says. "So it wasn't enough for us to demonstrate that the microbial nanowires are conductive and to show with physics the conduction mechanism, we had to determine the impact of this conductivity on the biology."
"We have now identified key components that make these hair-like pili we call nanowires conductive and have demonstrated their importance in the biological electron transport. This time we relied more on genetics. I think most biologists are more comfortable with genetics rather than physics," Lovley adds.
"From my perspective, this is huge. It really clinches a big question. We overturned the major objection the biologists were making and confirmed the assumption in our earlier work, that real metallic-like conductivity is taking place."
Findings are described in an early online issue of mBio, the open-access journal of the American Society for Microbiology. In addition to Lovley, the UMass Amherst team includes first author Madeline Vargas, with Nikhil Malvankar, Pier-Luc Tremblay, Ching Leang, Jessica Smith, Pranav Patel, Oona Snoeyenbos-West and Kelly Nevin.
In 2011, Lovely's group discovered a fundamental, previously unknown property of pili in Geobacter. They found that electrons are transported along the pili via the same metallic-like conductivity found in synthetic organic mate
|Contact: Janet Lathrop|
University of Massachusetts at Amherst