Single-Cell Study Uncovers Unexpected Viral Behavior
Researchers from the University of Illinois Urbana-Champaign and Texas A&M University have made a surprising discovery about how viruses infect bacteria. Their study, published in Current Biology, shows that when multiple viruses attack a single bacterial cell, they can actually hinder each other’s ability to enter the cell.
This finding challenges previous assumptions about viral infection and could have significant implications for our understanding of bacterial infections and the development of new treatments.
The Intricate Dance of Viral Invasion
Bacteriophages, or phages for short, are viruses that infect bacteria. They’ve been studied for over 50 years, but this new research brings unprecedented detail to our understanding of the infection process.
Ido Golding, a physics professor at the University of Illinois, explains: “The field of phage biology has seen an explosion over the last decade because more researchers are realizing the significance of phages in ecology, evolution, and biotechnology. This work is unique because we looked at phage infection at the level of individual bacterial cells.”
The researchers used cutting-edge fluorescent labeling techniques to track both the protein shells of phages and their genetic material as they infected Escherichia coli bacteria. This allowed them to observe, for the first time, exactly how many phages attached to a bacterial cell and how many successfully injected their genetic material.
What they found was unexpected. As more phages attached to a bacterial cell’s surface, proportionally fewer of them managed to inject their genetic material into the cell. In other words, the phages were getting in each other’s way.
“Our data shows that the first stage of infection, phage entry, is an important step that was previously underappreciated,” Golding said. “We found that the coinfecting phages were impeding each other’s entry by perturbing the electrophysiology of the cell.”
Why it matters: This discovery could have far-reaching implications for our understanding of bacterial infections and how to combat them. It suggests that the initial stage of viral entry into a cell is more complex and important than previously thought. This could lead to new approaches for preventing or treating bacterial infections, as well as improving our ability to use phages for beneficial purposes in biotechnology and medicine.
The study also sheds light on how phages decide between two different infection strategies: lysis (where the virus forces the cell to produce more viruses until it bursts) and lysogeny (where the virus integrates its genome into the bacterial one and remains dormant). The number of phages that successfully enter a cell influences this decision, which in turn affects the outcome of the infection.
These findings open up new avenues for research in bacterial electrophysiology – the study of electrical properties of bacterial cells. Recent studies have shown that these electrical properties play a role in antibiotic resistance, and now this research suggests they’re also crucial in viral infections.
Looking ahead, the research team plans to use even more advanced imaging techniques to examine the molecular details of phage entry. “Even though the resolution of our techniques was good, what was happening at the molecular level was still largely invisible to us,” Golding said. “We are looking at using the Minflux system at the Carl R. Woese Institute for Genomic Biology. The plan is to examine the same process but apply a better experimental method. We’re hoping that this will help us find new biology.”
As our understanding of the complex interactions between viruses and bacteria grows, we may uncover new strategies for combating harmful infections and harnessing the power of beneficial microbes. This research represents an important step forward in that journey, revealing the unexpected intricacies of the microbial world.
