College of Grain Oil and Food Science, Henan University of Technology, 140 Songshan South Road, Zhengzhou 450052, China.
Spectrochim Acta A Mol Biomol Spectrosc. 2011 Feb;78(2):676-80. doi: 10.1016/j.saa.2010.11.047. Epub 2010 Dec 7.
In order to study the different effects of ginsenosides with similar structures, research on interactions between ginsenoside Rg1, Re and lysozyme was carried out by electrospray ionization mass spectrometry (ESI-MS) and molecular docking. The 1:1 and 2:1 noncovalent complexes of ginsenosides and lysozyme were observed in the mass spectra and the dissociation constants for them were directly calculated based on peak intensities of lysozyme and its noncovalent complexes with ginsenosides. The results showed that the 1:1 complex of ginsenoside Rg1 and lysozyme was more stable than that of ginsenoside Re and lysozyme. As the acidity increased, the stabilities of the 1:1 complexes of Rg1, Re and lysozyme both decreased. Interestingly, as the acidity increased, the stability of the 2:1 complex of Rg1 and lysozyme increased while that of Re decreased. From the result of molecular docking, ginsenosides interacted with the active sites of lysozyme. And the stability of the complexes could be affected by the conformation changes of lysozyme as acidity increased.
为了研究结构相似的人参皂苷的不同作用，通过电喷雾电离质谱（ESI-MS）和分子对接研究了人参皂苷 Rg1、Re 与人溶菌酶之间的相互作用。在质谱中观察到了人参皂苷与人溶菌酶的 1:1 和 2:1 非共价复合物，并直接根据溶菌酶及其与人参皂苷的非共价复合物的峰强度计算了它们的离解常数。结果表明，人参皂苷 Rg1 与人溶菌酶的 1:1 复合物比人参皂苷 Re 与人溶菌酶的更稳定。随着酸度的增加，Rg1、Re 和溶菌酶的 1:1 复合物的稳定性均降低。有趣的是，随着酸度的增加，Rg1 与人溶菌酶的 2:1 复合物的稳定性增加，而 Re 的稳定性降低。从分子对接的结果来看，人参皂苷与人溶菌酶的活性部位相互作用。并且随着酸度的增加，溶菌酶构象的变化可能会影响复合物的稳定性。
