Labile Zinc-Assisted Biological Phosphate Chemosensing and Related Molecular Logic Gating Interpretations
Autor: | Léo Kaufman, Yonghwang Ha, Kibong Kim, David G. Churchill |
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Rok vydání: | 2011 |
Předmět: |
Circular dichroism
Magnetic Resonance Spectroscopy GTP' Stereochemistry Metal ions in aqueous solution Molecular Probe Techniques Gating Guanosine Diphosphate Pyrophosphate Fluorescence Phosphates Inorganic Chemistry chemistry.chemical_compound Adenosine Triphosphate Tubulin Physical and Theoretical Chemistry Aqueous solution Circular Dichroism Phosphate Adenosine Diphosphate Zinc Crystallography chemistry Zinc Compounds Spectrophotometry Ultraviolet |
Zdroj: | Inorganic Chemistry. 51:928-938 |
ISSN: | 1520-510X 0020-1669 |
Popis: | Herein, molecular fluorescence 'OFF-ON' behavior with aqueous addition of biological phosphate and Zn(2+) is studied with Zn(2)(slys)(2)Cl(2) [H(2)slys = 6-amino-2-{(2-hydroxybenzylidene)amino}hexanoic acid], a fluorescent water-soluble complex, using various spectroscopic tools (e.g., (31)P NMR, UV-vis, 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. (31)P 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: PPiATP ≈ GTP (3.35 ± 0.77 × 10(4) M(-1) for PPi, 7.73 ± 1.79 × 10(3) M(-1) for ATP, 9.21 ± 2.88 × 10(3) M(-1) for GTP over 1·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. |
Databáze: | OpenAIRE |
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