Bacteria and viruses: a network of intestinal relationships


The balance of human intestinal microbiota, consisting of hundreds of bacterial species and phages (bacteria viruses), is crucial to good health. A research team, including scientists from the CNRS1 and the Institut Pasteur, has characterised the phage-bacterial interaction networks of the microbiota in ten healthy individuals, with unprecedented precision. Scientists detected several hundred bacterial and phage genomes and identified the thousands of interactions that bind them by quantifying the contacts between the DNA molecules of viruses and their hosts. This method has the advantage of providing exhaustive data from limited biological samples. The results were then analysed using algorithms similar to those applied to the study of social media communities. This panorama of relationships between bacteria and phages could be applied to therapies involving intestinal microbiota, such as faecal transplantation and phagotherapy. The approach used in the study, recently published in eLife, could also lead to more precise analyses of terrestrial and marine ecosystems.

Network of interactions between phages (blue) and bacteria (green) present in a human microbiota. The lines represent the assignment of a phage to its bacterial host.
© Martial Marbouty / Romain Koszul


  • 1Researchers from the Génétique des génomes unit (CNRS/Institut Pasteur) and the Bioinformatics and Biostatistics Hub (CNRS/Institut Pasteur)

MetaHiC phage-bacteria infection network reveals active cycling phages of the healthy human gut. Martial Marbouty, Agnès Thierry, Gaël A. Millot and Romain Koszul. eLife, 26 February 2021. DOI: 10.7554/eLife.60608


Romain Koszul
CNRS and Institut Pasteur researcher
Martial Marbouty
CNRS researcher
Elie Stecyna
CNRS press officer