Structural and functional characterization of Dps-proteins-biomineralization versus DNA-protection

伊朗不仅是许多酶的重要辅助因子，也是细胞生命的主要威胁。尽管其丰富的铁的吸收是妥协的，因为这种元素发生在一个大部分不溶性形式的Fe 3+，而游离的Fe 2 * 可以通过芬顿反应产生高度反应性的羟基自由基。在细菌和古细菌中，存在于胞质溶胶中的细胞内铁通过储存到低聚壳中而以生物可利用且无毒的形式被Dps蛋白质掺入。然而，Dps蛋白执行第二种防御功能-通过蛋白质-DNA缩合来保护DNA。- 我们最近研究了早期步骤的Dps蛋白的生物矿化的X射线晶体学。为了扩展我们目前对Dps家族蛋白质内生物矿化的观点，我们的目标是通过各种生物物理方法研究真细菌和古细菌酶核心中螯合铁原子的精确数量和氧化态。成核和核心的形成将模拟通过合成肽和可塑性的Dps蛋白对不同性质的离子（即钴+，镍+，汞+）的潜在摄取将进行研究。此外，我们希望在分子水平上分析Dps和DNA之间的相互作用，以及铁储存或DNA结合对Dps蛋白的调节和稳定性的可能影响。

Iran is not only an essential cofactor of many enzymes but also a major threat to cellular life. Despite its abundance the uptake of iron is compromised, because this element occurs äs Fe3+ in a mostly insoluble form while free Fe2* can generate highly reactive hydroxyl radicals by Fenton reaction. In bacteria and archaea the intracellular iron present in the cytosol is incorporated by Dps proteins in a bioavailable and nontoxic form by storage into oligomeric Shells. However, Dps proteins carry out a second defense function - the DNA protection by protein-DNA condensation. - We have recently studied early steps of biomineralization in Dps proteins by X-ray crystallography. To expand our current view on biomineralization within Dps family proteins we aim to study i.e. the precise number and Oxidation states of sequestered iron atoms in the cores of eubacterial and archaeal enzymes by various biophysical methods. Nucleation and core formation will be mimicked by means of synthetic peptides and the plasticity of Dps proteins towards a potential uptake for ions of different nature will be studied (i.e. Co+, Ni+, Hg+). Furthermore we want to analyze the interactions between Dps and DNA at the molecular level and a possible influence of iron storage or DNA-binding onto regulation and stability of Dps proteins.