Single‐Sided Competitive Axial Coordination of G‐Quadruplex/Hemin as Molecular Switch for Imaging Intracellular Nitric Oxide. Issue 2 (11th December 2018)

• Record Type: Journal Article
• Authors: Zhang, Lei; Zhou, Jun; Ma, Fengjiao; Wang, Quanbo; Xu, Hui; Ju, Huangxian; Lei, Jianping
• Is Part Of: Chemistry. Volume 25:Issue 2(2019)
• Page Start: 490
• Page End: 494
• Publication Date: 2018-12-11
• Subjects: axial coordination -- biosensors -- fluorescent probes -- G-quadruplex-hemin -- imaging; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201804897
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: 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. Abstract : Single‐sided axial coordination of G‐quadruplex‐hemin complex shows significant advantages of highly reactive monomeric hemin, a single available axial site, and a strong binding capacity compared with uncomplexed hemin, which can be used as a molecular switch for in situ imaging and detection of intracellular NO through competitive axial coordination after assembly with a designed fluorescent ligand and conjugated with the nanocarrier.