Bacteriophages, or phages for short, are viruses that infect and destroy bacteria. They are constantly evolving, and bacteria are constantly evolving to defend themselves against them. Researchers have been looking at ways to use phages as allies against antibiotic-resistant bacteria, that are becoming an increasing threat.
To study the mechanisms of how phages infect bacteria, researchers at Chalmers University of Technology have turned to helium ion microscopy, a technique that allows them to image the atomic structures of biological materials in three dimensions.
"For the first time, we've been able to observe and structurally analyze the complex interactions that occur as a phage penetrates and takes over a bacterium. It's a revolutionary advance that's providing us with brand new insights into how phages infect bacteria and how we can develop new strategies to fight antibiotic resistance," says Martin Hentschel, Professor at the Department of Biology and Biological Engineering at Chalmers and head of this study.
The research team used helium ion microscopy to create three-dimensional images of the phage infecting and destroying the bacterium. They were able to see the individual molecules of the phage, the way the phage attaches to the bacterium, and the way it injects its DNA into the bacterium.
The researchers also found that the phage uses a special enzyme to dissolve the bacterium's outer membrane. This enzyme, called a holin, is a potential target for new antibiotics that could prevent phages from infecting bacteria.
"This is just the beginning. Now that we can visualize how phages infect and destroy bacteria at this atomic level, we can start to design new strategies to inhibit this process and develop new antibiotics that are effective against antibiotic-resistant bacteria," says Martin Hentschel.
