Metal Machine Cells

Researchers at Berkeley Labs and The Molecular Foundry have created a direct channel to transport electrons through a cell’s membrane, connecting the cell to “an external acceptor through a well-defined path.” This new molecular roadmap could be a way of “interfacing synthetic devices with living organisms,” creating cells that read and respond to electrical signals from an “external acceptor.” The genetic key to the electron pathway is found in the metal-reducing bacteria that evolved mechanisms to breathe iron oxide from the deep sea or soil. This model of “direct charge transfer to inorganic materials” is linked to a strand of DNA that contains the information to make the electron conduit. Berkeley’s research team cloned the extracellular electron transfer DNA chain of a metal-reducing bacteria and inserted it into a strain of E Coli. The engineered E.coli was found to efficiently reduce iron and iron oxide particles faster than E.coli alone.

The interfacing of living systems and electronics opens up possibilities in energy and biotechnology by harnessing “‘capabilities of photo- and chemical energy conversion, chemical synthesis, self-assembly and repair,’” part of a “larger Department of Energy project on domesticating life at the cellular and molecular level.” The Molecular Foundry research team plans to engineer photosynthetic bacteria to create self-replicating solar batteries and find new applications for “‘melding the living and non-living worlds.’”

image: "Engineering Nanoparticles for maximum Strength" by Lawrence Berkeley National Laboratory via Creative Commons Licensing.