Direct Evidence of Divalent Manganese Ion‐Induced DNA Condensation at Room Temperature

Whether manganese ion can induce DNA condensation at room temperature has not been clarified. In this study, direct evidence of Mn2+ ion‐induced DNA condensation is provided by single‐molecule measurements and atomic force microscopy characterization. It is shown that elevated temperature is not a requirement to induce DNA condensation, but helps to promote the process at the ensemble level. The finding suggests the failure of the Manning theory in explaining Mn2+‐DNA interactions and refreshes the view that divalent metal ions cannot cause DNA condensation. The localized binding of Mn2+ on DNA is believed to induce condensation. image