Plasmid-based system for high-level gene expression and antisense gene knockdown in Bartonella henselae

Area of Science:

• Microbiology
• Molecular Biology
• Bacterial Pathogenesis

Background:

• Bartonella henselae is a facultative intracellular bacterium responsible for cat scratch disease.
• Understanding gene expression in B. henselae is crucial for developing effective therapeutic strategies.
• Limited tools exist for genetic manipulation and gene expression studies in B. henselae.

Purpose of the Study:

• To develop novel plasmid vectors for studying gene expression in Bartonella henselae.
• To utilize these vectors for gene knockdown via antisense RNA.
• To investigate the role of ompR in B. henselae invasion of endothelial cells.

Main Methods:

• Construction and characterization of six broad-host-range plasmid vectors.
• Expression of a beta-galactosidase reporter gene in B. henselae.
• Generation of antisense RNA targeting the ompR gene.
• Assessment of bacterial invasion of human endothelial cells following gene knockdown.

Main Results:

• Successfully established plasmid vectors for gene expression in B. henselae.
• Demonstrated the efficacy of antisense RNA for gene knockdown of ompR.
• Achieved a significant reduction (over 60%) in B. henselae invasion of human endothelial cells by targeting ompR.

Conclusions:

• The developed plasmid vectors are effective tools for genetic studies in B. henselae.
• OmpR is a key regulator of B. henselae invasion into endothelial cells.
• Antisense RNA-mediated gene knockdown is a viable strategy to inhibit bacterial pathogenesis.