Light-driven artificial enzymes for selective oxidation of guanosine triphosphate using water-soluble POSS network polymers
作者:Jong-Hwan Jeon、Kazuo Tanaka、Yoshiki Chujo
DOI:10.1039/c4ob01115e
日期:——
The light-driven artificial enzymes were constructed to realize unnatural reactions concerning bio-significant molecules. In this manuscript, the guanosine triphosphate (GTP)-selective oxidation is reported using the network polymers composed of polyhedral oligomeric silsesquioxane (POSS). We synthesized the water-soluble POSS network polymer containing the naphthyridine ligands to capture GTP inside the networks and the ruthenium complexes to oxidize the captured GTP under light irradiation. Initially, the binding affinities of the guanosine nucleosides to the naphthyridine ligand inside the POSS network polymer were evaluated from the emission quenching experiments. Accordingly, it was observed that the naphthyridine ligand can form the stable complex only with GTP (Ka = 5.5 × 106 M−1). These results indicate that only GTP can be captured by the network polymer. Next, the photo-catalytic activity of the ruthenium complex-modified POSS network polymer was investigated. Finally, it was revealed that the network polymer can decompose GTP efficiently under light irradiation. This is the first example, to the best of our knowledge, to offer not only the GTP-selective host polymers but also the light-driven artificial enzyme for GTP oxidation.
通过构建光驱动人工酶来实现有关重要生物分子的非自然反应。本手稿报道了利用多面体低聚硅倍半氧烷(POSS)组成的网络聚合物进行三磷酸鸟苷(GTP)选择性氧化。我们合成了含有萘啶配体的水溶性 POSS 网络聚合物,可在网络内捕获 GTP,而钌配合物则可在光照射下氧化捕获的 GTP。首先,通过发射淬灭实验评估了鸟苷核苷与 POSS 网络聚合物内的萘啶配体的结合亲和力。结果表明,萘啶配体只能与 GTP 形成稳定的复合物(Ka = 5.5 × 106 M-1)。这些结果表明,只有 GTP 能被网络聚合物捕获。接着,研究了钌络合物修饰的 POSS 网络聚合物的光催化活性。结果表明,该网络聚合物在光照射下能有效分解 GTP。据我们所知,这是第一个不仅提供 GTP 选择性宿主聚合物,而且还提供光驱动 GTP 氧化人工酶的实例。