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Updated: Sep 19, 2025
11:10
High-throughput Assay to Phenotype Salmonella enterica Typhimurium Association, Invasion, and Replication in Macrophages
Published on: August 11, 2014
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Salmonella exploits host- and bacterial-derived β-alanine for replication inside host macrophages
Shuai Ma1, Bin Yang1, Yuyang Sun1
1National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China.
Elife
|June 19, 2025
Summary
Beta-alanine is essential for Salmonella growth within host macrophages. Its synthesis or acquisition is critical for Salmonella
Area of Science:
- Microbiology
- Pathogen Biology
- Nutritional Biochemistry
Background:
- Salmonella is a significant foodborne pathogen causing systemic infections by replicating within host macrophages.
- The specific nutrient requirements for intracellular Salmonella growth remain largely undefined.
- Understanding these requirements is crucial for developing novel therapeutic strategies.
Purpose of the Study:
- To identify essential nutrients for Salmonella replication within macrophages.
- To elucidate the role of beta-alanine in Salmonella intracellular growth and virulence.
- To investigate the mechanism by which beta-alanine impacts Salmonella pathogenesis.
Main Methods:
- Investigated the requirement of beta-alanine for Salmonella replication in macrophages.
- Analyzed the expression of beta-alanine synthesis gene (panD) during infection.
- Assessed the impact of panD mutation on Salmonella virulence in vivo.
- Examined the effect of beta-alanine on zinc transporter gene (znuABC) expression.
Main Results:
- Beta-alanine acquisition or de novo synthesis is critical for Salmonella replication inside macrophages.
- Salmonella-infected macrophages show decreased beta-alanine levels, suggesting host acquisition.
- Upregulation of panD and impaired replication in panD mutants highlight the importance of de novo synthesis.
- Beta-alanine enhances Salmonella virulence partly by increasing zinc uptake via znuABC.
Conclusions:
- Beta-alanine is a key nutrient for Salmonella intracellular replication and systemic infection.
- The panD gene, essential for beta-alanine synthesis, is a potential target for controlling Salmonella.
- Targeting beta-alanine metabolism offers a novel strategy against Salmonella infections.
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