目的:探究影响人类免疫缺陷病毒Ⅰ型(human immunodeficiency virus type 1,HIV-1)非核苷类逆转录酶抑制剂6-苄基-1-乙氧甲基-5-异丙基尿嘧啶[6-benzyl-1-(ethoxymethyl)-5-isopropyluracil,MKC-442]及其类似物抗病毒活性的主要分子微观结构因素。方法:针对45个MKC-442及其类似物,利用遗传函数逼近法(genetic function approximation,GFA)构建10个抗HIV-1活性与优选的分子结构描述符之间的二维定量构效关系(2-dimensional quantitative structure-activity relationship,2D-QSAR)模型,从中挑选出最优模型并对其进行验证,据此阐明影响MKC-442及其类似物抗HIV-1活性的主要微观结构因素。结果:最优2D-QSAR模型的非交叉验证相关系数r2为0.7845,交叉验证相关系数q2为0.6958,预测验证相关系数r2pred为0.8415,表明其具有较高的预测能力和稳定性。结论:研究表明,MKC-442及其类似物抗HIV-1活性主要与描述符JursFNSA2,ShadowYZ,DipoleX,Kappa3AM和CHIV3P相关,为MKC-442及其类似物的进一步结构修饰打下了一定的理论基础。
Neuraminidase(NA) plays a biologically vital role in the replication of influenza virus, and NA inhibitors(NAIs) are most widely used in the clinical anti-flu therapy. NA of 2009 H1 N1 influenza virus(09 N1) possesses a different substrate-binding cavity compared with other NA subtypes, making 09 N1 a more appropriate starting point for the discovery of potent 09 N1 inhibitors. As natural products are of great structural diversity, research on the interaction between natural NAIs and 09 N1 can throw light on the design of new structural NAIs. In this study, we, for the first time, conducted molecular docking procedure with GOLD on 10 natural inhibitors to 09 N1, and acquired their binding modes with 09 N1. The docking results showed that the active site S1 was important in the binding of NAIs to 09 N1. Then five scaffolds were extracted from these NAIs with interactions to site S1, and these could be used in the structural modification of NAIs. Besides, we found that the addition of H-bonding interaction with the active site could improve the NA inhibitory activity of NAIs, and it might be the reason why the approved NAIs showed high efficiency. Two terminal hydrophobic sites(Terminal 1 and Terminal 2) with no interactions to the approved NAI zanamivir were found in the 09 N1 active cavity, and four NAIs were first found to bind with the terminals. Till now, there are few studies on the meaning of Terminal 2 in the binding of NAI to NA, which could be a new direction for the rational design of NAIs.
