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Development and Assessment of Intracellular Infection Models for Staphylococcus aureus
Published on: January 17, 2025
Staphylococcus aureus surface protein SasG contributes to intercellular autoaggregation of Staphylococcus aureus
Makoto Kuroda1, Ryuta Ito, Yoshikazu Tanaka
1Laboratory of Bacterial Genomics, Center for Pathogen Genomics, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan. makokuro@nih.go.jp
Biochemical and Biophysical Research Communications
|November 6, 2008
Summary
Staphylococcus aureus surface protein G (SasG) facilitates cell aggregation and biofilm formation. The SasG-A domain
Area of Science:
- Microbiology
- Bacterial Pathogenesis
- Protein Structure-Function
Background:
- Staphylococcus aureus surface protein G (SasG) is a cell surface protein crucial for bacterial adhesion and biofilm formation.
- SasG possesses a cell-wall sorting motif, indicating its role in anchoring to the bacterial surface.
Purpose of the Study:
- To investigate the role of SasG in Staphylococcus aureus cell aggregation and biofilm formation.
- To elucidate the oligomerization properties of the SasG protein domains and their contribution to bacterial interactions.
Main Methods:
- Construction and analysis of a sasG mutant.
- Native-PAGE and in vitro formaldehyde cross-linking experiments.
- Recombinant protein expression and characterization of SasG domains.
Main Results:
- The sasG mutant exhibited significantly reduced cell aggregation and biofilm formation compared to wild-type.
- The A domain of SasG demonstrated homo-oligomerization into an octameric structure.
- The B domain of SasG did not show homo-oligomerization.
Conclusions:
- The A domain of SasG is essential for intercellular autoaggregation through homo-oligomerization.
- SasG-mediated autoaggregation likely enhances Staphylococcus aureus adherence to host tissues during infection.
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