The flagella of Helicobacter pylori work like specialised propellers driven by a high-torque rotating motor. These convert chemical energy generated from proton gradients across the bacterial membrane into mechanical rotation. These help the bacteria to navigate the thick mucus of the human stomach to travel from highly acidic areas (pH 2) to areas with a more neutral pH (pH 5.5 to 7.5) where they thrive best.
Using high-resolution electron microscopy imaging, scientists have recently characterised the architecture of this motor which form the building block of flagella, and my god, does this look like a beautiful feat of engineering. 🦠⚙️