Grant R A, Filman D J, Finkel S E, Kolter R, Hogle J M
Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA.
Nat Struct Biol. 1998 Apr;5(4):294-303. doi: 10.1038/nsb0498-294.
The crystal structure of Dps, a DNA-binding protein from starved E. coli that protects DNA from oxidative damage, has been solved at 1.6 A resolution. The Dps monomer has essentially the same fold as ferritin, which forms a 24-mer with 432 symmetry, a hollow core and pores at the three-fold axes. Dps forms a dodecamer with 23 (tetrahedral) point group symmetry which also has a hollow core and pores at the three-folds. The structure suggests a novel DNA-binding motif and a mechanism for DNA protection based on the sequestration of Fe ions.
Dps是一种来自饥饿大肠杆菌的DNA结合蛋白，可保护DNA免受氧化损伤，其晶体结构已在1.6埃分辨率下解析出来。Dps单体与铁蛋白的折叠方式基本相同，铁蛋白形成具有432对称性的24聚体，有一个中空核心和位于三重轴上的孔。Dps形成具有23（四面体）点群对称性的十二聚体，同样有一个中空核心和位于三重轴上的孔。该结构揭示了一种新的DNA结合基序以及基于铁离子螯合作用的DNA保护机制。
