Scientists unravel the secret of the bacterial scourge – a milestone for microbiology!

Scientists unravel the secret of the bacterial scourge – a milestone for microbiology!

An international research team led by the Humboldt University of Berlin has made significant progress in understanding microbial motility. On July 9, 2025, the scientists published their results in the scientific journalNature Microbiologyand thus shed light on the structure of the bacterial flagellum, a puzzle that has puzzled microbiology since the 1950s. Deciphering the structure of this complex macromolecular machine could have far-reaching implications for the development of new antimicrobial strategies and synthetic nanomachines, such as hu-berlin.de reported.

The bacterial flagellum, which consists of a basal body, a hook and a long extracellular filament, enables microorganisms such as Salmonella enterica and Campylobacter jejuni to move in a targeted manner. The researchers also clarified the structure and insertion of flagellin molecules into the filament. Cryo-electron microscopy was used to image the flagella of Salmonella with near atomic resolution.

Revolutionizing microbiology

A central point of the discovery is the visualization of the flagellum in an active and correctly folded state. Rosa Einenkel, lead author of the paper, describes the mechanism of incorporating new flagellin molecules as a “molecular ballet” in which the filament cap rotates and adjusts to correctly insert the molecules. In addition, the connection between the hook and the filament acts as a buffer for mechanical stress, which strongly influences the technique of bacterial locomotion.

The importance of these findings is not only evident in microbiology. Researchers are using similar principles to understand biological nanomachines that perform different essential tasks in cells. For example, ribosomes, as protein complexes, regulate the assembly of proteins from their building blocks, while chloroplasts in plant cells convert solar energy into chemical energy, which drives all life processes, such as simplyscience.ch explained.

Future perspectives

Understanding how biological systems work is crucial to medicine and pharmacology. There is potential here to develop new antibiotics and medicines. In this context, researchers at Osaka University have also conducted studies on the assembly of the export gate apparatus in Salmonella to find out how bacteria infect eukaryotic cells and to identify new drug targets, according to this scienceaq.com.

The bacterial flagellum is considered one of the oldest nanomachines in biology and plays a key role in the movement of bacteria. The functionally similar structures to the injection devices of bacteria open up new perspectives in medical research, as the scientific knowledge about these structures could represent promising targets for the development of new drugs.