Reversible DNA condensation drives natural transformation - PubMed
4 hours ago
- #antibiotic resistance
- #natural transformation
- #DNA condensation
- Natural transformation facilitates the spread of antibiotic resistance among bacteria.
- ComEA, a DNA receptor, is essential for transporting external DNA into the periplasm via an unknown mechanism.
- Single-molecule optical tweezers and electron microscopy reveal that ComEA forms dynamic oligomers on DNA, switching between two conformations based on local concentration.
- Sparse ComEA decoration leads to bridging oligomers that condense DNA and generate sub-pN pulling forces.
- Full ComEA decoration results in non-bridging oligomers that decondense DNA and cannot generate force.
- Mutations favoring either bridging or non-bridging conformations cause transformation deficiency in Bacillus subtilis, indicating both condensation and decondensation are mechanistically important.
- ComEA reversibly condenses DNA during natural transformation, first pulling DNA into the periplasm and then promoting transport into the cytoplasm.