Bacteria use wrapping flagella to tunnel through microscopic passages, research reveals

Researchers have discovered how bacteria break through spaces barely larger than themselves, by wrapping their flagella around their bodies and moving forward. Using a microfluidic device that mimics insect gut channels, the team revealed a remarkable "flagellar wrapping" motion that lets symbiotic bacteria pass through 1-micrometer-wide tunnels. Genetic manipulation and mathematical calculation showed that the flexibility of a tiny joint in the flagellum, called the hook, is crucial for this screw-like movement and even determines whether the bacteria can successfully infect their insect hosts.