The Yersinia pestis autotransporter YapC mediates host cell binding, autoaggregation and biofilm formation

Area of Science:

• Microbiology
• Molecular Biology
• Pathogen Virulence

Background:

• Yersinia pestis is a pathogenic bacterium responsible for plague.
• Autotransporter proteins are important virulence factors in Gram-negative bacteria.
• YapC shares homology with the enterotoxigenic Escherichia coli adhesin TibA.

Purpose of the Study:

• To investigate the functional activities of the Yersinia pestis autotransporter protein YapC.
• To determine YapC's role in bacterial adhesion, autoaggregation, and biofilm formation.
• To assess the in vivo relevance of YapC during Yersinia pestis infection.

Main Methods:

• Expression of YapC in a non-pathogenic E. coli strain (AAEC185).
• Assessing bacterial adhesion to macrophage (RAW264.7) and epithelial (HEp-2) cell lines.
• Evaluating autoaggregation and biofilm formation capabilities.
• Generating a yapC deletion mutant in Y. pestis strain KIM5 for phenotypic analysis.
• Quantitative reverse transcription PCR (RT-PCR) to assess yapC expression levels.

Main Results:

• YapC expression in E. coli mediated attachment to both RAW264.7 and HEp-2 cells.
• YapC facilitated autoaggregation and biofilm formation by E. coli.
• Deletion of yapC in Y. pestis did not affect adhesion or biofilm formation.
• RT-PCR indicated low in vitro expression of yapC in Y. pestis.

Conclusions:

• YapC exhibits adhesive, autoaggregative, and biofilm-forming properties in vitro.
• The lack of a clear phenotype in the Y. pestis DeltayapC mutant may be due to low yapC expression or functional redundancy.
• YapC has potential roles in Yersinia pestis pathogenesis that warrant further investigation.