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Analysis of Fucosylated Human Milk Trisaccharides in Biotechnological Context Using Genetically Encoded Biosensors
Published on: April 13, 2019
Fucose sensing regulates bacterial intestinal colonization.
Alline R Pacheco1, Meredith M Curtis, Jennifer M Ritchie
1Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9048, USA.
Nature
|November 20, 2012
Summary
Enterohaemorrhagic Escherichia coli (EHEC) uses fucose, a sugar abundant in the gut, to control its virulence. This fucose-sensing system, FusKR, is crucial for EHEC colonization and pathogenicity in the mammalian intestine.
Area of Science:
- Microbiology
- Molecular Biology
- Gastroenterology
Background:
- The mammalian gut is a competitive microbial environment.
- Pathogen colonization requires nutrient scavenging, signal sensing, and virulence gene regulation.
- Enterohaemorrhagic Escherichia coli (EHEC) utilizes inter-kingdom signaling for virulence.
Purpose of the Study:
- To identify novel chemical sensing systems in EHEC.
- To investigate the role of fucose sensing in EHEC virulence and colonization.
- To elucidate the interaction between microbiota and EHEC in the gut.
Main Methods:
- Characterization of a novel two-component system, FusKR (FusK sensor kinase, FusR response regulator).
- Analysis of FusK's fucose-sensing capabilities.
- Assessment of FusKR system's requirement for EHEC intestinal colonization.
- Investigating the role of Bacteroides thetaiotaomicron in activating EHEC virulence via fucose.
Main Results:
- A novel fucose-sensing two-component system, FusKR, was identified in EHEC.
- FusKR controls the expression of virulence and metabolic genes.
- The FusKR system is essential for robust EHEC colonization of the mammalian intestine.
- Bacteroides thetaiotaomicron cleaves fucose from mucin, activating EHEC's FusKR system and modulating virulence gene expression.
Conclusions:
- EHEC employs the FusKR system to sense and utilize fucose, a readily available nutrient in the gut.
- Microbiota-driven fucose availability influences EHEC pathogenicity and metabolism.
- This study reveals a mechanism by which EHEC adapts to the host environment by sensing host-derived signals made available by commensal bacteria.
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