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The Mannose Phosphotransferase System in Enterococcus lactis Is Essential for Gastrointestinal Colonization
Linan Xu1,2, Xiangpeng Yang1, Xingshuai Li1
1College of Agriculture and Forestry, Linyi University, Linyi, People's Republic of China.
Molecular Microbiology
|December 23, 2025
Summary
Enterococcus lactis uses a specific sugar pathway for gut colonization. This mannose-utilization PTS is crucial for its survival and colonization in the mouse gastrointestinal tract.
Area of Science:
- Microbiology
- Gut Microbiome Research
- Bacterial Physiology
Background:
- Enterococcus lactis is a common gut commensal, recently distinguished from the opportunistic pathogen Enterococcus faecium.
- Understanding E. lactis colonization mechanisms is limited due to its recent classification.
- Carbohydrate utilization is vital for microbial survival and niche adaptation in the competitive gut environment.
Purpose of the Study:
- To investigate the role of carbohydrate metabolism in E. lactis intestinal colonization.
- To characterize a conserved PTS gene cluster in E. lactis and its function.
Main Methods:
- Genetic analysis of a conserved PTS gene cluster in E. lactis.
- Construction and characterization of gene-deletion mutants.
- Assessment of bacterial growth on different sugars (mannose).
- Evaluation of GI tract colonization in a mouse model.
Main Results:
- A conserved PTS gene cluster, important for mannose utilization, was identified in E. lactis.
- Gene-deletion mutants showed significantly reduced growth on mannose.
- Mutants were unable to colonize the mouse GI tract.
Conclusions:
- The mannose-utilization PTS plays a critical role in E. lactis intestinal colonization.
- This finding provides insight into carbohydrate-driven colonization strategies of gut bacteria.
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