Structural Bioinformatics Team, Division of Structural and Synthetic Biology, Center for Life Science Technologies, RIKEN, 1-7-22, Suehiro, Tsurumi, Yokohama, 230-0045 (Japan).
Drug Design Laboratory, Yokohama City University, 1-7-29, Suehiro, Tsurumi, Yokohama, 230-0045 (Japan).
Angew Chem Int Ed Engl. 2015 Aug 17;54(34):9857-60. doi: 10.1002/anie.201503575. Epub 2015 Jul 1.
We have engineered a metal-binding site into the novel artificial β-propeller protein Pizza. This new Pizza variant carries two nearly identical domains per polypeptide chain, and forms a trimer with three-fold symmetry. The designed single metal ion binding site lies on the symmetry axis, bonding the trimer together. Two copies of the trimer associate in the presence of cadmium chloride in solution, and very high-resolution X-ray crystallographic analysis reveals a nanocrystal of cadmium chloride, sandwiched between two trimers of the protein. This nanocrystal, containing seven cadmium ions lying in a plane and twelve interspersed chloride ions, is the smallest reported to date. Our results indicate the feasibility of using rationally designed symmetrical proteins to biomineralize nanocrystals with useful properties.
我们在新型人工β-发夹蛋白 Pizza 中设计了一个金属结合位点。这种新的 Pizza 变体每个多肽链携带两个几乎相同的结构域，并形成具有三重对称的三聚体。设计的单个金属离子结合位点位于对称轴上，将三聚体连接在一起。在溶液中存在氯化镉的情况下，两个三聚体的副本结合在一起，非常高分辨率的 X 射线晶体学分析揭示了夹在两个三聚体蛋白之间的氯化镉纳米晶体。该纳米晶体含有七个位于一个平面上的镉离子和十二个穿插的氯离子，是迄今为止报道的最小的。我们的结果表明，使用合理设计的对称蛋白来生物矿化具有有用性质的纳米晶体是可行的。
