Yersinia pseudotuberculosis produces a cytotoxic necrotizing factor

Area of Science:

• Microbiology
• Cell Biology
• Bacterial Pathogenesis

Background:

• Multinucleation in host cells can be induced by bacterial toxins.
• Escherichia coli cytotoxic necrotizing factor (CNF) is a known inducer of multinucleation.
• The presence of similar activities in other bacterial species is largely unexplored.

Purpose of the Study:

• To investigate the multinucleation-inducing activity in Yersinia pseudotuberculosis.
• To characterize the nature of this activity and its relationship to known factors like E. coli CNF.
• To identify the genetic basis of the observed activity.

Main Methods:

• Preparation of cell extracts from Yersinia pseudotuberculosis.
• Incubation of HEp-2 cells with bacterial extracts.
• Testing the effect of antibodies against E. coli CNF type 1.
• Nucleotide sequencing of the Yersinia cnf gene.

Main Results:

• Yersinia pseudotuberculosis extracts induced multinucleation in HEp-2 cells.
• This activity was independent of the Yersinia 70-kb virulence plasmid.
• Antibodies neutralizing E. coli CNF type 1 did not inhibit the Yersinia-induced effect.
• The Yersinia cnf gene showed 65.1% nucleotide sequence identity to the E. coli cnf gene.

Conclusions:

• Yersinia pseudotuberculosis possesses an intrinsic activity that induces multinucleation in host cells.
• This activity is distinct from E. coli CNF type 1, suggesting different mechanisms or targets.
• The Yersinia cnf gene is likely responsible for this novel multinucleation-inducing activity.