Molecular Design of Artificial Proteins Bearing Novel Structural Motif by Utilizing an Unnatural Amino Acid

利用非天然氨基酸进行具有新颖结构基序的人工蛋白质的分子设计

基本信息

批准号：
14380292
负责人：
ISHIDA Hitoshi
金额：
$ 9.6万
依托单位：
Kitasato University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2004
项目状态：
已结题

项目摘要

The purpose of this work is to design and synthesize artificial proteins, which consist of peptides containing an unnatural and coordinating amino acid, 5'-amino-2,2'-bipyridine-5-carboxylic acid. The peptides containing a couple of residues of the unnatural amino acid are expected to coordinate with a metal ion, affording the artificial proteins with unique structural motifs. In the synthesis of peptides, the dipeptide units, which were separately prepared, were introduced into the common solid phase synthetic methods ; otherwise the synthesis was difficult due to its less reactive amino group. The 21-mer peptides with three residues of the unnatural amino acids were successfully synthesized by the methodology. Furthermore, formation of the iron(II) complexes by reacting the peptides with iron(II) ion was observed in absorption spectra, showing Metal-to-Ligand Charge Transfer (MLCT) band at 541 nm. On the other hand, if ruthenium(II) ion was used, the artificial proteins had ruthenium tris(bipyridine) type complexes as the core, which were expected to appear photo-functions, such as emission, photo-catalytic, and photo-induced electron transfer abilities. Since there are, however, few works on ruthenium tris(5,5'-disubstitueted-2,2'-bipyridine) complexes, we synthesized various ruthenium complexes of the unnatural amino acid derivatives and 5,5'-diamide-2,2'-bipyridines and investigated their photochemical properties. In particular, these complexes were found to act as sensors for a variety of anions by strongly binding with them via cooperative hydrogen bonding between the amide hydrogen (NH) in three the ligands and anions.

这项工作的目的是设计和合成人工蛋白质，该蛋白质由含有非天然配位氨基酸 5'-氨基-2,2'-联吡啶-5-羧酸的肽组成。含有几个非天然氨基酸残基的肽有望与金属离子配位，从而提供具有独特结构基序的人造蛋白质。在肽的合成中，将单独制备的二肽单元引入常见的固相合成方法中；否则，由于其氨基反应性较低，合成很困难。通过该方法成功合成了含有三个非天然氨基酸残基的21聚体肽。此外，在吸收光谱中观察到肽与铁 (II) 离子反应形成铁 (II) 络合物，显示 541 nm 处的金属到配体电荷转移 (MLCT) 谱带。另一方面，如果使用钌(II)离子，人造蛋白质以钌三(联吡啶)型配合物为核心，预计会出现光功能，如发射、光催化和光诱导等。电子转移能力。然而，由于三(5,5'-二取代-2,2'-联吡啶)钌配合物的研究很少，我们合成了非天然氨基酸衍生物和5,5'-二酰胺-2,2的各种钌配合物。 '-联吡啶并研究了它们的光化学性质。特别是，这些复合物被发现可作为各种阴离子的传感器，通过三个配体中的酰胺氢（NH）和阴离子之间的协同氢键与它们强烈结合。