State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P.R. China.
School of Chemistry and Molecular Engineering, Institute of, Advanced Synthesis, Jiangsu National Synergetic Innovation Center for, Advanced Materials, Nanjing Tech University, Nanjing, 211816, P.R. China.
Chemistry. 2019 Jan 7;25(2):490-494. doi: 10.1002/chem.201804897. Epub 2018 Dec 11.
Axial coordination is a crucial biological process to regulate biomolecules' functions in natural enzymes. However, it is a great challenge to determine the single or dual axial interaction between the metal center of enzymes and the ligand. In this work, a controllable axial coordination system was developed based on G-quadruplex/hemin complex by designing a series of fluorescent derivatives. The mechanism on axial coordination of G-quadruplex/hemin with coumarin-imidazole ligands was proposed to be single-sided, and led to fluorescence quenching of ligands. Upon addition of nitric oxide, the fluorescence of ligands was recovered through competitive axial coordination, providing a "signal on" strategy for signal transduction. More significantly, the fluorescent imaging of intracellular nitric oxide was achieved after conjugating with gold nanoparticles. Also, the proposed protocol provided a smart strategy to monitor the relationship between nitric oxide and p53 protein activity in living cells.
轴向配位是调节天然酶中生物分子功能的关键生物过程。然而，确定酶的金属中心与配体之间的单一或双重轴向相互作用是一个巨大的挑战。在这项工作中，通过设计一系列荧光衍生物，开发了基于 G-四链体/血红素复合物的可控轴向配位体系。提出了 G-四链体/血红素与香豆素-咪唑配体的轴向配位机制为单侧，导致配体的荧光猝灭。加入一氧化氮后，通过竞争性轴向配位恢复配体的荧光，为信号转导提供了“信号开启”策略。更重要的是，通过与金纳米粒子缀合实现了细胞内一氧化氮的荧光成像。此外，所提出的方案为监测活细胞中一氧化氮与 p53 蛋白活性之间的关系提供了一种智能策略。
