Structural Rearrangement of Dps-DNA Complex Caused by Divalent Mg and Fe Cations.

ABSTRACT: Two independent, complementary methods of structural analysis were used to elucidate the effect of divalent magnesium and iron cations on the structure of the protective Dps-DNA complex. Small-angle X-ray scattering (SAXS) and cryo-electron microscopy (cryo-EM) demonstrate that Mg2+ ions block the N-terminals of the Dps protein preventing its interaction with DNA. Non-interacting macromolecules of Dps and DNA remain in the solution in this case. The subsequent addition of the chelating agent (EDTA) leads to a complete restoration of the structure of the complex. Different effect was observed when Fe cations were added to the Dps-DNA complex; the presence of Fe2+ in solution leads to the total complex destruction and aggregation without possibility of the complex restoration with the chelat

SUBMITTER: Dadinova L 

PROVIDER: S-EPMC8199988 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature