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Quantifying Yersinia pseudotuberculosis Type III Secretion System Activity Following Iron Starvation and Anaerobic Growth
Published on: May 31, 2024
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Increased plasmid copy number is essential for Yersinia T3SS function and virulence
He Wang1, Kemal Avican1, Anna Fahlgren2
1Umeå Centre for Microbial Research (UCMR), Department of Molecular Biology, Umeå University, SE-901 87 Umeå, Sweden. Laboratory for Molecular Infection Medicine Sweden (MIMS), Department of Molecular Biology, Umeå University, SE-901 87 Umeå, Sweden.
Science (New York, N.Y.)
|July 2, 2016
Summary
Pathogenic bacteria like Yersinia pseudotuberculosis increase virulence plasmid copy numbers during infection. This boosts the type III secretion system (T3SS), essential for establishing bacterial infections.
Area of Science:
- Microbiology
- Bacterial Pathogenesis
- Molecular Biology
Background:
- Pathogenic bacteria utilize diverse virulence mechanisms for infection.
- Yersinia species employ a type III secretion system (T3SS) encoded on a virulence plasmid.
- The regulation of virulence factors during infection is a key area of study.
Purpose of the Study:
- To investigate novel virulence strategies in Yersinia pseudotuberculosis.
- To understand the role of plasmid copy number in bacterial infection.
- To elucidate the relationship between plasmid replication and T3SS function.
Main Methods:
- Genetic analysis of Yersinia pseudotuberculosis.
- Plasmid copy number quantification during infection.
- Assessment of type III secretion system (T3SS) expression and function.
- Investigating the coupling between plasmid replication and T3SS activity.
Main Results:
- Yersinia pseudotuberculosis up-regulates its virulence plasmid copy number during infection.
- Increased plasmid copy number is essential for Yersinia virulence.
- Elevated plasmid gene dosage significantly enhances T3SS expression and function.
- A direct, tight coupling exists between plasmid replication and T3SS activity.
Conclusions:
- Yersinia employs a novel virulence strategy involving increased plasmid copy number.
- This mechanism enhances T3SS function, crucial for establishing infection.
- The identified regulatory pathway offers insights into bacterial environmental sensing.
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