腺苷-3’,5’-环磷酸-氧蒽酮希夫碱的合成及其与LC3B的绑定结合

Synthesis of Schiff base of adenosine 3’, 5’-cyclicmonophosphoric acid with xanthone and its binding to LC3B

目的:设计合成具有LC3B绑定功能的腺苷-3’,5’-环磷酸-氧蒽酮希夫碱(S1),研究其对LC3B的作用机制。方法:以紫外-可见光谱表征S1和LC3B的分子结合动力学,运用一级反应动力学进行数据拟合,采用荧光光谱测定二者的结合常数和热力学常数,推导出分子结合机制。结果:S1在160 s快速结合LC3B,结合过程满足一级反应动力学方程和药物的定比转运规律,热力学研究发现S1与LC3B结合的吉布斯自由能变化小于零,为自发结合过程,焓变小于0进一步表明S1和LC3B通过静电吸引结合,导致S1的荧光猝灭,S1通过希夫碱的C=N官能团与LC3B发生相互作用。结论:S1可以自发地通过静电作用绑定细胞自噬标志物LC3B。

Objective:To design the potential proteolysis targeting chimeras(PROTAC)drug S1 synthesized from adenosine 3’,5’-cyclicmonophosphoric acid and xanthone.Methods:The binding kinetics of S1 and LC3B was characterized by UV-Vis spectroscopy.The resulted data were fitted to first order reaction kinetics.The binding constants and thermodynamic constants of the S1-LC3B complex were determined by fluorescence spectroscopy,and the molecular binding mechanism was deduced.Results:S1 bound to LC3B fast within 160 s.The binding kinetics obeyed the first order reaction kinetics equation and specific transport rule.Thermodynamic study found that the Gibbs free energy change was negative,indicating a spontaneous binding process.And negative enthalpy change suggested a static attraction between S1 and LC3B.Such course was attributed to the interaction of C=N at S1 with LC3B,resulting in fluorescence quenching.Conclusion:The Schiff base S1 can spontaneously bind to LC3B.