Researchers identify genes aiding bacterial defense against phages

Researchers at the University of Toronto have identified nine new genes that help bacteria defend against phages, which are viruses that infect them. This breakthrough was published in the journal Nature Microbiology. The researchers focused on a bacterium called Vibrio parahaemolyticus, known for causing gastroenteritis in people who consume raw seafood. Their study involved analyzing DNA from sediment samples collected from tanks at Toronto's Ripley Aquarium. Using advanced bioinformatics tools, the team discovered these defense genes in a specific part of the bacterial genome known as the integron. Integrons are regions where bacteria can gather beneficial genes, such as those that help them resist antibiotics. By cloning the identified genes and testing them against various phages, the researchers were able to confirm the existence of nine unique defense systems. They noted that activating these genes requires energy, so bacteria only turn them on in response to signals from their environment. Interestingly, four of the nine defense genes were activated when bacteria sensed they were in crowded conditions, a phenomenon known as quorum sensing. This is especially important since viral infections can pose a greater threat when bacteria are abundant. The findings suggest that targeting these phage defense systems could enhance phage therapy, a potential treatment for bacterial infections that might become crucial as antibiotic resistance grows. Since integrons are found in many bacterial species, this research opens doors for new therapeutic approaches in both fisheries and human medicine.