
Nucleic Acids Research, Journal Year: 2025, Volume and Issue: 53(5)
Published: Feb. 11, 2025
Protein-primed DNA replication is a unique mechanism, bioorthogonal to other known modes. It relies on specialised single-stranded (ssDNA)-binding proteins (SSBs) stabilise ssDNA intermediates by unknown mechanisms. Here, we present the structural and biochemical characterisation of P12, an SSB from bacteriophage PRD1. High-resolution cryo-electron microscopy reveals that P12 forms unique, cooperative filament along ssDNA. Each protomer binds phosphate backbone 6 nucleotides in sequence-independent manner, protecting nuclease degradation. Filament formation driven intrinsically disordered C-terminal tail, facilitating binding. We identify residues essential for interaction link ssDNA-binding ability toxicity host cells. Bioinformatic analyses place fold as distinct branch within OB-like family. This work offers new insights into protein-primed lays foundation biotechnological applications.
Language: Английский