权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Structures and functions of reaction spaces constructed using metalloprotiens

使用金属蛋白质构建的反应空间的结构和功能

基本信息

批准号：
16074208
负责人：
WATANABE Yoshihito
金额：
$ 37.76万
依托单位：
Nagoya University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research on Priority Areas
财政年份：
2004
资助国家：
日本
起止时间：
2004 至 2007
项目状态：
已结题

项目摘要

Last year, we have specified the amino acid residues responsible for capturing Pd2+ ions on the interior surface of ap-ferritin by X-ray crystal structural studies. In addition, we have examined the residues which ligate to Au3+ ions and found that some of the Au ion binding sites in apo-ferritin are different from those of Pd ions with different coordi-nation structures. On the basis of these observation, we have prepared two type of metal nano-clusters, i.e., alloy and core/shell as shown in Schem 1. In the co-reduction, Au and Pd ions coexist in the apo-ferritin cage. The number of each ion in the cage is regulated by the affinity of each ions to its specific amino acid residues. Consequently, the alloy nano-particle was composed of 133 Au atoms and 165 Pd atoms ((AuPd)・apo-ferritin). On the other hand, we have successfully prepared Au-core/Pd-shell([Au] (Pd)) and Pd-core/Au-shell ([Pd] (Au)) types of nano-particles composed of 201 Au atoms/305 Pd atoms and 169 Au atoms/65Pd atoms, respectively. Among those apo-ferritin composites, [Au] (Pd) apo-ferritin shows the highest catalytic activity for the hydrogenation of olefins.In a separate experiment, we have examined a possible incorporation of organometallic compounds such as [Pd(allyl)C1]2 and [Rh(norbornadiene)C1]2 in apo-ferritin. The crystal structure of Pd(allyl)・apo-ferritin clearly shows that the allyl group ligates to Pd ion in apo-ferritin.

去年，我们已经指定的氨基酸残基负责捕获Pd 2+离子的AP-铁蛋白的内表面上的X-射线晶体结构研究。此外，我们还研究了与Au ~（3+）离子结合的残基，发现脱辅基铁蛋白中的某些Au离子结合位点与Pd离子的结合位点不同，具有不同的配位结构。在此基础上，我们制备了两种类型的金属纳米团簇，合金和核/壳，如方案1所示。在共还原中，Au和Pd离子共存于脱铁铁蛋白笼中。笼中每个离子的数量由每个离子对其特定氨基酸残基的亲和力调节。因此，合金纳米颗粒由133个Au原子和165个Pd原子（（AuPd）·apo-ferritin）组成。另一方面，我们成功地制备了由201个Au原子/305个Pd原子和169个Au原子/65个Pd原子组成的Au核/Pd壳（[Au]（Pd））和Pd核/Au壳（[Pd]（Au））型纳米粒子。在这些脱辅基铁蛋白复合物中，[Au]（Pd）脱辅基铁蛋白对烯烃的加氢反应表现出最高的催化活性.在一个单独的实验中，我们考察了金属有机化合物如[Pd（allyl）C1]2和[Rh（norbornadiene）C1]2在脱辅基铁蛋白中的可能掺入. Pd（allyl）·apo-ferritin的晶体结构清楚地表明，在apo-ferritin中，烯丙基与Pd离子连接。