Balance between fluorescence enhancement and association affinity in fluorescent heteroditopic indicators for imaging zinc ion in living cells.
Balance between fluorescence enhancement and association affinity in fluorescent heteroditopic indicators for imaging zinc ion in living cells.
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DOI：
10.1021/ic201728f
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发表时间：
2011-10-17
影响因子：
4.6
通讯作者：
Zhu L
中科院分区：
文献类型：
--
作者：
Kuang GC;Allen JR;Baird MA;Nguyen BT;Zhang L;Morgan TJ Jr;Levenson CW;Davidson MW;Zhu L
A fluorescent heteroditopic indicator for zinc(II) ion possesses two different zinc(II) binding sites. The sequential coordination of zinc(II) at the two sites can be transmitted into distinct fluorescence changes. In the heteroditopic ligand system that our group developed, the formations of mono- and di-zinc(II) complexes along an increasing gradient of zinc(II) concentration lead to fluorescence enhancement and emission bathochromic shift, respectively. The extents of these two changes determine the sensitivity, and ultimately, the effectiveness of the heteroditopic indicator in quantifying zinc(II) ion over a large concentration range. In this work, a strategy to increase the degree of fluorescence enhancement upon the formation of the mono-zinc(II) complex of a heteroditopic ligand under simulated physiological conditions is demonstrated. Fluorination of the pyridyl groups in the pentadentate N,N,N′-tris(pyridylmethyl)ethyleneamino group reduces the apparent pKa value of the high-affinity site, which increases the degree of fluorescence enhancement as the mono-zinc(II) complex is forming. However, fluorination impairs the coordination strength of the high-affinity zinc(II) binding site, which in the triply-fluorinated ligand reduces the binding strength to the level of the low-affinity 2,2′-bipyridyl. The potential of the reported ligands in imaging zinc(II) ion in living cells was evaluated. The subcellular localization properties of two ligands in five organelles were characterized. Both benefits and deficiencies of these ligands were revealed which provides directions for the near future in this line of research.
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影响因子：
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作者：
Chang, CJ;Nolan, EM;Lippard, SJ
通讯作者：
Lippard, SJ
影响因子：
4
作者：
Bozym, Rebecca A.;Thompson, Richard B.;Fierke, Carol A.
通讯作者：
Fierke, Carol A.
影响因子：
3.6
作者：
Dineley, KE;Malaiyandi, LM;Reynolds, IJ
通讯作者：
Reynolds, IJ
影响因子：
15
作者：
Burdette, SC;Frederickson, CJ;Lippard, SJ
通讯作者：
Lippard, SJ
影响因子：
15
作者：
Hirano, T;Kikuchi, K;Nagano, T
通讯作者：
Nagano, T