The SARS-CoV-2 belongs to Coronaviridae family infects host cells by the interaction of its spike glycoprotein and angiotensin-converting enzyme 2 (ACE 2) of host cells. Upon entry, the virus uses its RNA dependent RNA polymerase (NSP12) for transcribing its genome to survive in the cell and spread its infection. The protein sequences of receptor-binding domain (RBD) of spike glycoprotein, and NSP12 exhibits high homology in the family of Coronoviridae and are ideal candidates for the development of anti-coronaviral drugs. In the quest to identify inhibitory molecules against these proteins, we searched several molecules that are present in naturally occurring medicinal plants database. Andrographolide which is largely present in the leaf extracts of Andrographis paniculata (AP) and is known to exhibit antiviral, antibacterial, and stabilizes Th1/Th2/Th17 responses; taking this clue, we used in silico approaches to see the binding of andrographolide to RBD and NSP12 molecules. Our docking results showed very strong affinity of andrographolide to RBD and NSP12 of the SARS-CoV-2 virus with dock scores of −10.3460 for RBD and −10.7313 for NSP12 indicating andrographolide acts as an inhibitor of RBD and NSP12. These unique properties of andrographolide, AP extract, can be tested as anti-coronaviral drug.

中文翻译：

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穿心莲内酯通过计算机模拟方法与 SARS-CoV-2 的刺突糖蛋白和 RNA 依赖性 RNA 聚合酶 (NSP12) 结合：抗冠状病毒药物开发中的可能分子

SARS-CoV-2属于冠状病毒科，通过其刺突糖蛋白与宿主细胞的血管紧张素转换酶2（ACE 2）相互作用来感染宿主细胞。进入细胞后，病毒利用其 RNA 依赖性 RNA 聚合酶 (NSP12) 转录其基因组，以便在细胞中生存并传播感染。刺突糖蛋白受体结合域（RBD）和NSP12的蛋白序列在冠状病毒科中表现出高度同源性，是开发抗冠状病毒药物的理想候选者。为了寻找针对这些蛋白质的抑制分子，我们搜索了天然存在的药用植物数据库中存在的几种分子。穿心莲内酯主要存在于穿心莲 (AP) 的叶提取物中，已知具有抗病毒、抗菌作用，并稳定 Th1/Th2/Th17 反应；根据这一线索，我们使用计算机方法来观察穿心莲内酯与 RBD 和 NSP12 分子的结合。我们的对接结果显示，穿心莲内酯与 SARS-CoV-2 病毒的 RBD 和 NSP12 具有很强的亲和力，RBD 的对接分数为 -10.3460，NSP12 的对接分数为 -10.7313，表明穿心莲内酯充当 RBD 和 NSP12 的抑制剂。AP 提取物穿心莲内酯的这些独特特性可以作为抗冠状病毒药物进行测试。