Cells, tiny as they are, are packed with molecular machinery that investigators can exploit for their own purposes. German scientists now report that certain protein complexes in fava beans have characteristics that might make the complexes useful as valves in microfluidic devices.
“It’s always difficult to find actuators, or moving parts, that can be controlled neatly and will do what you want them to do on a small scale,” says Winfried S. Peters, a biologist at Justus Liebig University in Giessen, Germany. He, Michael Knoblauch, and their colleagues report in the September Nature Materials that they’ve identified just such an actuator. In the beans, the needle-shaped protein complexes are situated in so-called sieve tubes, where they control the plant’s flow of sugar-bearing fluid.