Bacteria can sense when they bump into things and reverse direction, a new study in Nature Microbiology reports.

Researchers found that Pseudomonas aeruginosa, a common bacterium, changes course when it collides with obstacles. The behaviour helps it navigate crowded environments.

The study, published on October 6, reveals a simple mechanical sensing system. When the cell's front end hits something, it triggers a reversal of its swimming motor.

This collision-sensing helps bacteria move through soil, tissue and other tight spaces. It may also play a role in how infections spread through the body.

Scientists say understanding bacterial navigation could lead to better ways to fight harmful microbes or guide helpful ones.

The findings show that even single-celled organisms without brains can process physical feedback and adapt their movement.

The team observed the behaviour under microscopes in controlled lab tests. They tracked individual cells as they hit barriers and turned away.

Future work will test whether blocking this sensing makes infections easier to treat.