Enteric pathogens exploit the microbiota-generated nutritional environment of the gut

The mammalian gastrointestinal (GI) tract harbors a diverse collection of indigenous bacteria known as the microbiota. The number of bacterial cells within our bodies exceeds the number of our cells by one order of magnitude (3). Homeostasis of the microbiota is maintained by differential nutrient utilization and physical separation from the gut mucosa (4). However, environmental perturbations such as antibiotic treatment, changes in diet, and infection lead to substantial alterations in composition and structure of the microbiota, referred to as dysbiosis (5 - 8).