Labile Zinc-Assisted Biological Phosphate Chemosensing and Related Molecular Logic Gating Interpretations

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• 作者：Kibong Kim ; Yonghwang Ha ; L茅o Kaufman ; David G. Churchill
• 刊名：Inorganic Chemistry
• 出版年：2012
• 出版时间：January 16, 2012
• 年：2012
• 卷：51
• 期：2
• 页码：928-938
• 全文大小：617K
• 年卷期：v.51,no.2(January 16, 2012)
• ISSN：1520-510X

文摘

Herein, molecular fluorescence 鈥極FF鈥揙N鈥?behavior with aqueous addition of biological phosphate and Zn²⁺ is studied with Zn₂(slys)₂Cl₂ [H₂slys = 6-amino-2-{(2-hydroxybenzylidene)amino}hexanoic acid], a fluorescent water-soluble complex, using various spectroscopic tools (e.g., ³¹P NMR, UV鈥搗is, emission, and CD spectroscopy) at the micromolar level. Adduct-dependent fluorescence intensity changes can be interpreted as a two-input (cation/anion) implication molecular logic gating system. A displacement study of PPi from the dizinc complex is also reported. Diphosphate and triphosphate addition/displacements were also studied. ³¹P NMR spectroscopy shows gradual NMR peak shifts from bound ADP/GDP to free ADP/GDP with increasing [PPi]. In the emission spectrum, fluorescence quenching is shown: CD signal maxima decrease with addition of PPi. These displacement events are also tested with triphosphates (ATP, GTP), and their binding strength/displacement ability over ADP/GDP is quantified: PPi > ATP 鈮?GTP (3.35 卤 0.77 脳 10⁴ M^鈥? for PPi, 7.73 卤 1.79 脳 10³ M^鈥? for ATP, 9.21 卤 2.88 脳 10³ M^鈥? for GTP over 1路ADP). Many anions and cations were also screened for selectivity. Tubulin polymerization was assayed in the presence of 1 and its copper analogue which reflected a slight inhibition in polymerization.