Analysis of Element Composition of DNA-Protein Crystals In Vitro

Resumo

The universal response of Escherichia coli to stress is enhancing the synthesis of specific histone-like Dps proteins that bind bacterial DNA. As a result, two-dimensional and three-dimensional crystalline arrays can be observed in the cytoplasm of starving bacteria. Conditions for obtaining in vitro co-crystals of DNA-Dps were selected, and their elemental composition was studied using analytical electron microscopy. It was found that Dps in the co-crystal retains its ferritin-like activity; that is, it can stimulate the oxidation of Fe²⁺ ions to Fe³⁺ and facilitate the accumulation of iron in the form of Fe₂O₃ in the inner cavity of the oligomer.