Senthil V, Longworth J W, Ghiron C A, Grossweiner L I
Physics Department, Illinois Institute of Technology, Chicago 60616.
Biochim Biophys Acta. 1992 Jan 23;1115(3):192-200. doi: 10.1016/0304-4165(92)90053-w.
Absorption and fluorescence measurements of purified hypericin (HY) were made in various media. Photosensitization of two aqueous systems was investigated: resealed red blood cell membranes (ghosts) and hen lysozyme (Lys). Solubilization of HY by ghost membranes was shown by means of diffuse reflectance spectroscopy. Visible light irradiation of the ghosts incorporating HY led to lipid peroxidation with evidence of singlet oxygen involvement. A binding model applicable for insoluble ligands is indicative of strong HY binding to HSA. The HY-HSA complex photosensitized inactivation of Lys. The pseudo-first-order reaction kinetics with protection by azide ion are consistent with a Type II mechanism mediated by singlet oxygen. The results are discussed in the context of the HY photodynamic and antiretroviral activities.
在各种介质中对纯化的金丝桃素（HY）进行了吸收和荧光测量。研究了两种水性体系的光敏化作用：重封的红细胞膜（血影）和鸡溶菌酶（Lys）。通过漫反射光谱法显示了血影膜对HY的增溶作用。掺入HY的血影在可见光照射下导致脂质过氧化，有单线态氧参与的证据。适用于不溶性配体的结合模型表明HY与HSA有很强的结合。HY-HSA复合物使Lys发生光敏失活。在叠氮离子保护下的准一级反应动力学与单线态氧介导的II型机制一致。结合HY的光动力和抗逆转录病毒活性对结果进行了讨论。
