The first bite--profiling the predatosome in the bacterial pathogen Bdellovibrio

Area of Science:

• Microbiology
• Genomics
• Bacteriology

Background:

• Bdellovibrio bacteriovorus is a Gram-negative bacterium that preys on other Gram-negative bacteria.
• It shows potential as a biocontrol agent and living antibiotic against human, animal, and plant pathogens.
• The genetic basis of its predatory lifestyle is not fully understood.

Purpose of the Study:

• To identify genes and regulatory mechanisms involved in the predatory process of Bdellovibrio bacteriovorus HD100.
• To understand gene expression changes during early-stage prey infection and killing.

Main Methods:

• Differential gene expression analysis using mixed predator-prey mRNA.
• Comparison of gene expression during predation versus axenic (host-independent) growth.
• Monitoring gene expression at 30 minutes post-infection.

Main Results:

• Seven percent of Bdellovibrio genes were significantly upregulated during infection, suggesting roles in prey digestion.
• Five percent of genes were significantly downregulated, indicating involvement in the free-swimming attack phase.
• Identified genes of the 'predatosome' with predicted roles in prey killing and digestion.

Conclusions:

• This study provides the first post-genomic insights into the Bdellovibrio predatory process.
• Key genes involved in the initial attack and establishment within the prey bdelloplast were revealed.
• Findings illuminate the molecular machinery and genetic control of bacterial predation.