Abstract
Neonates are highly susceptible to infection with enteric pathogens, but the underlying mechanisms are not resolved. We show that neonatal chick colonization with Salmonella enterica serovar Enteritidis requires a virulence-factor-dependent increase in epithelial oxygenation, which drives pathogen expansion by aerobic respiration. Co-infection experiments with an Escherichia coli strain carrying an oxygen-sensitive reporter suggest that S. Enteritidis competes with commensal Enterobacteriaceae for oxygen. A combination of Enterobacteriaceae and spore-forming bacteria, but not colonization with either community alone, confers colonization resistance against S. Enteritidis in neonatal chicks, phenocopying germ-free mice associated with adult chicken microbiota. Combining spore-forming bacteria with a probiotic E. coli isolate protects germ-free mice from pathogen colonization, but the protection is lost when the ability to respire oxygen under micro-aerophilic conditions is genetically ablated in E. coli. These results suggest that commensal Enterobacteriaceae contribute to colonization resistance by competing with S. Enteritidis for oxygen, a resource critical for pathogen expansion.
Original language | English |
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Pages (from-to) | 128-139.e5 |
Journal | Cell Host and Microbe |
Volume | 25 |
Issue number | 1 |
DOIs | |
State | Published - 9 Jan 2019 |
Externally published | Yes |
Bibliographical note
Publisher Copyright:© 2018 Elsevier Inc.
Keywords
- Enterobacteriaceae
- Salmonella
- colonization resistance
- microbiota
- neonate
- oxygen