AimP Gene Review Notes
Colleague Question
Contact: sroux@lbl.gov
Key Interest: Phage cell-to-cell communication, lysogeny decision
Key Findings
Discovery of Viral Quorum Sensing
- FIRST viral quorum sensing system discovered (arbitrium system)
- Published in Nature 2017 - paradigm shift in phage biology
- Challenges view of phages as purely selfish genetic elements
Molecular Mechanism
- Peptide structure: 6 amino acids - SAIRGA
- Processing: AimX processes pre-AimP to mature peptide
- Receptor: AimR binds peptide, acts as transcriptional regulator
- Decision circuit: High peptide = lysogeny, Low peptide = lysis
Communication System
- Intercellular signaling: Phages communicate infection density
- Population-level coordination: Collective decision making
- Host manipulation: Uses host machinery for peptide processing
- Specificity: Different phages have distinct peptide sequences
Evolutionary Implications
- Arbitrium systems found in hundreds of Bacillus phages
- Suggests social evolution in viruses
- May coordinate with host stress responses
- Potential for cross-kingdom communication
GO Annotation Review
- Accepted peptide pheromone activity
- Added regulation of viral latency
- Emphasized intercellular signal transduction
Therapeutic Potential
- Target for controlling phage therapy outcomes
- Engineering controllable phage switches
- Understanding phage-bacteria population dynamics
- Potential anti-phage strategies
References
Remaining Questions
- Do different phage "languages" cross-talk?
- Can we predict lysis/lysogeny thresholds?
- How does this integrate with host quorum sensing?
- Are there anti-arbitrium systems in bacteria?