The molecular mechanisms of the ShosTA system in mediating anti-phage defense - PubMed
5 days ago
- #molecular mechanisms
- #anti-phage defense
- #toxin-antitoxin system
- The ShosTA system is a two-component toxin-antitoxin (TA) system consisting of ShosT (toxin) and ShosA (antitoxin).
- ShosT induces cell death, while ShosA neutralizes its toxic effects.
- Crystal structures reveal ShosT has a PRTase domain with noncanonical features and requires PRPP binding for toxicity.
- ShosA is a DprA-like protein functioning as a homodimer; its ssDNA-binding and dimerization are crucial for antitoxin activity.
- ShosA directly binds to RecA, an interaction essential for neutralizing ShosT and sensitive to ssDNA presence.
- The ShosTA system mediates abortive infection (Abi) in response to phage DNA, revealing its anti-phage defense mechanism.