Zika virus (ZIKV) NS2B-NS3 protease is a validated antiviral target as it is essential for maturation of viral proteins. However, its negatively charged active site hinders the development of orthosteric small-molecule inhibitors. Fragment-based drug discovery (FBDD) is a powerful tool to generate novel chemical starting points against difficult drug targets. In this study, we scre ened a fragment compound library against the Zika protease using a primary thermal shift assay and identified twenty-two fragments which (bind to and) stabilize the protease. We then determined the X-ray crystal structures of two hits from different classes, all of which bind to the S1 pocket of the protease. We confirmed that these two fragments bind to the protease without inducing significant conformational changes using solution NMR spectroscopy. These fragment scaffolds serve as the starting point for subsequent lead compound development.

中文翻译：

---

靶向寨卡病毒NS2B-NS3蛋白酶的小分子片段的鉴定和结构表征。

Zika病毒（ZIKV）NS2B-NS3蛋白酶是经过验证的抗病毒靶标，因为它对于病毒蛋白的成熟至关重要。但是，其带负电荷的活性位点阻碍了正构小分子抑制剂的发展。基于片段的药物发现（FBDD）是一种强大的工具，可以针对困难的药物靶标产生新的化学起点。在这项研究中，我们使用主要的热位移测定法筛选了针对Zika蛋白酶的片段化合物文库，并鉴定了22个片段（与之结合并使其稳定）。然后，我们确定了来自不同类别的两个命中的X射线晶体结构，所有这些命中均与蛋白酶的S1口袋结合。我们证实这两个片段结合到蛋白酶而不会使用溶液NMR光谱诱导显着的构象变化。