Humans are exposed to many types of bacteria daily, the majority of which are harmless. However, some bacteria are pathogenic, which means they can cause disease. An extremely common pathogenic bacterial infection is Helicobacter pylori (H. pylori) in the stomach, where it can lead to chronic inflammation (gastritis), ulcers, and even cancer. A group of researchers from Osaka University have determined a specific molecular mechanism that H. pylori uses to adapt to growing in the human stomach for long periods of time.