Metal binding at the Deinococcus radiodurans Dps-1 N-terminal metal site controls dodecameric assembly and DNA binding.

The prokaryotic DNA protection during starvation (Dps) proteins typically protect macromolecules against damaging agents via physical association with DNA and by oxidizing and sequestering iron. However, Deinococcus radiodurans Dps-1, which binds DNA with high affinity, fails to protect DNA against hydroxyl radicals due to iron leakage from the core, raising the question of how (•)OH-mediated damage to Dps-1-bound DNA is avoided. As shown here, Mn(II) inhibits ferroxidase activity, suggesting that ferroxidation may be prevented in vivo as D.