Abstract In order to study the interaction mechanism between meloxicam and pepsin, the interaction between meloxicam and pepsin was studied by fluorescence spectroscopy, UV-visible absorption spectroscopy, circular dichroism spectroscopy and molecular docking under physiological conditions (pH = 2.20). The results of spectral experiments showed that meloxicam quenched the intrinsic fluorescence of pepsin by static quenching, formed a stable complex at 1:1, and changed the conformation of pepsin. The thermodynamic results showed that the main force type of meloxicam and pepsin system was hydrophobic interaction. Molecular docking showed that there was a hydrogen bond in addition to hydrophobic interaction, and the best binding site between meloxicam and pepsin was near the catalytic active center of pepsin. The results showed that the combination of the meloxicam and pepsin changed the microenvironment of amino acid residues at the catalytic active center of pepsin. Under the experimental conditions, the protein binding rate of meloxicam to pepsin W(B) was 2.97–48.3%, indicating that the binding of meloxicam to pepsin had an effect on the number of free pepsin. The drug binding rate of the system W(Q) was 2.97–1.39%, indicating that the binding effect of meloxicam and pepsin on the number of free drug molecules was weak, so the binding effect would not have a significant effect on the efficacy of meloxicam.

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美洛昔康与胃蛋白酶相互作用的光谱和分子对接研究

摘要 为研究美洛昔康与胃蛋白酶的相互作用机制，采用荧光光谱、紫外-可见吸收光谱、圆二色光谱和分子对接等方法在生理条件下（pH=2.20）研究了美洛昔康与胃蛋白酶的相互作用。光谱实验结果表明，美洛昔康通过静态猝灭来猝灭胃蛋白酶的固有荧光，形成1:1的稳定复合物，改变胃蛋白酶的构象。热力学结果表明，美洛昔康和胃蛋白酶体系的主要作用力类型是疏水相互作用。分子对接表明，除疏水作用外，还存在氢键，美洛昔康与胃蛋白酶的最佳结合位点靠近胃蛋白酶的催化活性中心。结果表明，美洛昔康与胃蛋白酶的结合改变了胃蛋白酶催化活性中心氨基酸残基的微环境。在实验条件下，美洛昔康与胃蛋白酶W(B)的蛋白结合率为2.97-48.3%，表明美洛昔康与胃蛋白酶的结合对游离胃蛋白酶的数量有影响。系统W(Q)的药物结合率为2.97-1.39%，说明美洛昔康和胃蛋白酶对游离药物分子数的结合作用较弱，因此结合作用不会对药效产生显着影响。美洛昔康。表明美洛昔康与胃蛋白酶的结合对游离胃蛋白酶的数量有影响。系统W(Q)的药物结合率为2.97-1.39%，说明美洛昔康和胃蛋白酶对游离药物分子数的结合作用较弱，因此结合作用不会对药效产生显着影响。美洛昔康。表明美洛昔康与胃蛋白酶的结合对游离胃蛋白酶的数量有影响。系统W(Q)的药物结合率为2.97-1.39%，说明美洛昔康和胃蛋白酶对游离药物分子数的结合作用较弱，因此结合作用不会对药效产生显着影响。美洛昔康。