Bacteria’s bodies do whirlies to help them swim

Bacteria’s bodies were thought to be deadweight in the water. But new images and video show that the kidney-shaped Caulobacter crescentus swim with both their corkscrew-like propellers called flagella and their bodies. When the flagellum pushes a bacterium’s body, the cell whirls on a helical path, which can generate thrust and enhance the creatures’ movement, researchers report July 21 in the Proceedings of the National Academy of Sciences. The discovery may change the way scientists think about cell shape and its role in how bacteria swim in water and other fluids, such as mucus or semen.