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Structural Insights into Iron Ions Accumulation in Dps Nanocage.

ABSTRACT: Dps (DNA-binding protein from starved cells) is well known for the structural protection of bacterial DNA by the formation of highly ordered intracellular assemblies under stress conditions. Moreover, this ferritin-like protein can perform fast oxidation of ferrous ions and subsequently accumulate clusters of ferric ions in its nanocages, thus providing the bacterium with physical and chemical protection. Here, cryo-electron microscopy was used to study the accumulation of iron ions in the nanocage of a Dps protein from Escherichia coli. We demonstrate that Fe²⁺ concentration in the solution and incubation time have an insignificant effect on the volume and the morphology of iron minerals formed in Dps nanocages. However, an increase in the Fe²⁺ level leads to an increase in the proportion of larger clusters and the clusters themselves are composed of discrete ~1-1.5 nm subunits.

SUBMITTER: Chesnokov Y

PROVIDER: S-EPMC9140674 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature

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Structural Insights into Iron Ions Accumulation in Dps Nanocage.

Chesnokov Yury Y Mozhaev Andrey A Kamyshinsky Roman R Gordienko Alexander A Dadinova Liubov L

International journal of molecular sciences 20220510 10

Dps (DNA-binding protein from starved cells) is well known for the structural protection of bacterial DNA by the formation of highly ordered intracellular assemblies under stress conditions. Moreover, this ferritin-like protein can perform fast oxidation of ferrous ions and subsequently accumulate clusters of ferric ions in its nanocages, thus providing the bacterium with physical and chemical protection. Here, cryo-electron microscopy was used to study the accumulation of iron ions in the nanoc ...[more]

PMID: 35628121

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