Infection Mechanism - Blog Posts

How viruses infect bacteria: a tale of a tail

To infect bacteria, most bacteriophages employ a ‘tail’ that stabs and pierces the bacterium’s membrane to allow the virus’s genetic material to pass through. The most sophisticated tails consist of a contractile sheath surrounding a tube akin to a stretched coil spring at the nanoscale. When the virus attaches to the bacterial surface, the sheath contracts and drives the tube through it. All this is controlled by a million-atom baseplate structure at the end of the tail. EPFL scientists have now shown, in atomic detail, how the baseplate coordinates the virus’s attachment to a bacterium with the contraction of the tail’s sheath. The breakthrough has made the cover of Nature, and has important implications for science and medicine.

Nicholas M. I. Taylor, Nikolai S. Prokhorov, Ricardo C. Guerrero-Ferreira, Mikhail M. Shneider, Christopher Browning, Kenneth N. Goldie, Henning Stahlberg, Petr G. Leiman. Structure of the T4 baseplate and its function in triggering sheath contraction. Nature, 2016; 533 (7603): 346 DOI: 10.1038/nature17971

Bacteriophages are viruses that infect bacteria. Using state-of-the-art tools, EPFL scientists have described a million-atom “tail” that bacteriophages use to breach bacterial surfaces. The breakthrough has major implications for science and medicine, as bacteriophages are widely used in research.