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Structural highlights

Function

BFR_ECOLI Iron-storage protein, whose ferroxidase center binds Fe(2+) ions, oxidizes them by dioxygen to Fe(3+), and participates in the subsequent Fe(3+) oxide mineral core formation within the central cavity of the protein complex. The mineralized iron core can contain as many as 2700 iron atoms/24-meric molecule.^{[1] [2]} DPS_ECOLI During stationary phase, binds the chromosome non-specifically, forming a highly ordered and stable dps-DNA co-crystal within which chromosomal DNA is condensed and protected from diverse damages. It protects DNA from oxidative damage by sequestering intracellular Fe(2+) ion and storing it in the form of Fe(3+) oxyhydroxide mineral, which can be released after reduction. One hydrogen peroxide oxidizes two Fe(2+) ions, which prevents hydroxyl radical production by the Fenton reaction. Dps also protects the cell from UV and gamma irradiation, iron and copper toxicity, thermal stress and acid and base shocks. Also shows a weak catalase activity.^{[3] [4] [5] [6]}

See Also

• Ferritin 3D structures

References

1. ↑ Yang X, Le Brun NE, Thomson AJ, Moore GR, Chasteen ND. The iron oxidation and hydrolysis chemistry of Escherichia coli bacterioferritin. Biochemistry. 2000 Apr 25;39(16):4915-23. PMID:10769150
2. ↑ Baaghil S, Lewin A, Moore GR, Le Brun NE. Core formation in Escherichia coli bacterioferritin requires a functional ferroxidase center. Biochemistry. 2003 Dec 2;42(47):14047-56. PMID:14636073 doi:http://dx.doi.org/10.1021/bi035253u
3. ↑ Almiron M, Link AJ, Furlong D, Kolter R. A novel DNA-binding protein with regulatory and protective roles in starved Escherichia coli. Genes Dev. 1992 Dec;6(12B):2646-54. PMID:1340475
4. ↑ Wolf SG, Frenkiel D, Arad T, Finkel SE, Kolter R, Minsky A. DNA protection by stress-induced biocrystallization. Nature. 1999 Jul 1;400(6739):83-5. PMID:10403254 doi:http://dx.doi.org/10.1038/21918
5. ↑ Nair S, Finkel SE. Dps protects cells against multiple stresses during stationary phase. J Bacteriol. 2004 Jul;186(13):4192-8. PMID:15205421 doi:http://dx.doi.org/10.1128/JB.186.13.4192-4198.2004
6. ↑ Ceci P, Cellai S, Falvo E, Rivetti C, Rossi GL, Chiancone E. DNA condensation and self-aggregation of Escherichia coli Dps are coupled phenomena related to the properties of the N-terminus. Nucleic Acids Res. 2004 Nov 8;32(19):5935-44. Print 2004. PMID:15534364 doi:http://dx.doi.org/32/19/5935