Dipartimento di Scienze della vita e dell'ambiente. Università degli Studi di Cagliari, Cittadella Universitaria di Monserrato, SS-554, Monserrato, Cagliari, Italy.
Dipartimento di Chimica e Tecnologie del Farmaco, Istituto Pasteur-Fondazione Cenci-Bolognetti, "Sapienza" Università di Roma, p.le Aldo Moro 5, I-00185, Rome, Italy.
Antiviral Res. 2023 Sep;217:105697. doi: 10.1016/j.antiviral.2023.105697. Epub 2023 Aug 9.
For RNA viruses, RNA helicases have long been recognized to play critical roles during virus replication cycles, facilitating proper folding and replication of viral RNAs, therefore representing an ideal target for drug discovery. SARS-CoV-2 helicase, the non-structural protein 13 (nsp13) is a highly conserved protein among all known coronaviruses, and, at the moment, is one of the most explored viral targets to identify new possible antiviral agents. In the present study, we present six diketo acids (DKAs) as nsp13 inhibitors able to block both SARS-CoV-2 nsp13 enzymatic functions. Among them four compounds were able to inhibit viral replication in the low micromolar range, being active also on other human coronaviruses such as HCoV229E and MERS CoV. The experimental investigation of the binding mode revealed ATP-non-competitive kinetics of inhibition, not affected by substrate-displacement effect, suggesting an allosteric binding mode that was further supported by molecular modelling calculations predicting the binding into an allosteric conserved site located in the RecA2 domain.
对于 RNA 病毒，RNA 解旋酶在病毒复制周期中一直被认为起着至关重要的作用，它们有助于病毒 RNA 的正确折叠和复制，因此成为药物发现的理想靶点。SARS-CoV-2 解旋酶（非结构蛋白 13，nsp13）是所有已知冠状病毒中高度保守的蛋白，目前是研究最多的病毒靶点之一，旨在寻找新的可能的抗病毒药物。在本研究中，我们提出了六种二酮酸（DKAs）作为 nsp13 抑制剂，能够阻断 SARS-CoV-2 nsp13 的酶功能。其中四种化合物能够在低微摩尔范围内抑制病毒复制，并且对其他人类冠状病毒如 HCoV229E 和 MERS-CoV 也具有活性。结合模式的实验研究表明，抑制作用具有非竞争性的 ATP 动力学，不受底物置换效应的影响，这表明存在一种别构结合模式，分子建模计算进一步支持了这一模式，预测结合到位于 RecA2 结构域中的一个保守的别构结合位点。
