Science | The benefits of Escherichia coli
Infection and intestinal damage can trigger severe muscle wasting and loss of fat in mice. How this happens is poorly understood. Palaferri Schieber et al. discovered a protective Escherichia coli strain in their mouse colony. Mice intestinally colonized with the E. coli and infected with the food-poisoning bug Salmonella or with the lung pathogen Burkholderia did not waste away. Without the E. coli, similarly infected mice became fatally ill. The protective E. coli stimulated an innate immune mechanism that ensured that muscle-signaling pathways were not damaged by infection. Thus, the friendly E. coli allowed its host to tolerate and survive the pathogens.