Could we work together with our bacteria to stop infection?

As microbes have become increasingly resistant to antibiotics and antimicrobials scientists have become interested in new solutions to the growing superbug crisis, including the use of defensive microbes and faecal transplants. In new research, Oxford University scientists have developed a lab-based approach, creating positive co-dependent relationships between hosts and bacteria, quickly - termed 'mutualisms'. These lab-developed bacterial relationships demonstrate how microbes can work with their hosts to prevent infection. Defensive host-microbe relationships are prevalent in nature across plants and animals, including humans. The mutual benefit comes from the host benefiting from the protection of the bacteria, and the bacteria then benefiting from the host being a healthy living environment - allowing it to accumulate further over time. In a study published in Evolution Letters, scientists from Oxford's Department of Zoology worked with the University of Bath to test whether these defensive host-microbe 'mutualisms' could evolve from scratch to protect against attack from harmful and infectious parasites. The team tracked the evolution of a nematode worm host and a gut bacterium (Enterococcus faecalis) with the potential to protect against more pathogenic bacterial infection. After just a few short weeks of evolution, changes in both the worm and gut bacteria resulted in the species working together and ultimately forging a mutually beneficial alliance, protecting them both from attacks from parasites.