School of Chemistry and Environmental Science, Henan Normal University, Mu Ye District, Xinxiang, PR China.
Spectrochim Acta A Mol Biomol Spectrosc. 2010 Jan;75(1):261-6. doi: 10.1016/j.saa.2009.10.021. Epub 2009 Oct 21.
The molecular mechanism of the binding of norfloxacin (NRF) to trypsin was investigated by fluorescence, synchronous fluorescence and UV-vis absorbance spectroscopy and molecular modeling at physiological conditions. The quenching mechanism and the binding mode were investigated in terms of the association constants and basic thermodynamic parameters. The results of spectroscopic measurements suggested that NRF have a strong ability to quench the intrinsic fluorescence of trypsin through static quenching procedure. Moreover, fluorescence experiments were also performed at different values of pH to elucidate the effect of pH on the binding. The NRF-trypsin complex was stabilized by hydrophobic forces and hydrogen bonding, via tryptophan residue as indicated from the thermodynamic parameters, which was consistent with the results of molecular docking and accessible surface area calculations.
在生理条件下，通过荧光、同步荧光和紫外可见吸收光谱以及分子模拟研究了诺氟沙星（NRF）与胰蛋白酶结合的分子机制。根据结合常数和基本热力学参数，研究了猝灭机制和结合模式。光谱测量结果表明，NRF 具有通过静态猝灭过程强烈猝灭胰蛋白酶固有荧光的能力。此外，还在不同 pH 值下进行了荧光实验，以阐明 pH 值对结合的影响。通过热力学参数表明，NRF-胰蛋白酶复合物是通过疏水作用力和氢键稳定的，涉及色氨酸残基，这与分子对接和可及表面积计算的结果一致。
