Understanding the Structure of the Type Three Secretion System Needle Tip in Salmonella
Author Information
Author(s): Lunelli Michele, Hurwitz Robert, Lambers Jutta, Kolbe Michael
Primary Institution: Max Planck Institute for Infection Biology, Berlin, Germany
Hypothesis
How does the Salmonella SipD interact with PrgI and deoxycholate, and what are the mechanistic consequences of the assembly of the T3SS needle tip complex?
Conclusion
The study reveals that the T3SS needle tip complex binds deoxycholate, which may inhibit the secretion of virulence factors and thus prevent bacterial infection.
Supporting Evidence
- Binding of bile salts to the SipD:PrgI interface may inhibit T3SS function.
- The T3SS needle tip complex binds deoxycholate with micromolar affinity.
- Five copies of the needle subunit PrgI and SipD form the T3SS needle tip complex.
- Structural analysis revealed major conformational changes in both SipD and PrgI during complex formation.
Takeaway
Scientists studied how a part of bacteria called the T3SS needle tip works and found that it can grab onto certain substances in our gut, which might stop the bacteria from making us sick.
Methodology
The researchers used X-ray crystallography and surface plasmon resonance to analyze the structure and binding interactions of the T3SS needle tip proteins.
Digital Object Identifier (DOI)
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