Mutualistic interactions between Escherichia coli and Bifidobacterium bifidum enable degradation of human milk oligosaccharides in healthy infants

The development of the human gut microbiota during infancy is marked by frequent colonization of Enterobacteriaceae, a bacterial family notoriously associated with various diseases. Yet, despite their prominence in the absence of illness, their exact ecological role during healthy maturation of the infant gut remains poorly explored. Here, we analyse longitudinal stool samples from healthy, term-born, breastfed neonates (n=41) at two, six, and eleven months post-delivery, as well as microbiota of related mothers (n=30) with shotgun metagenomic sequencing, complemented by novel computational approaches and experimentation.