Dengue virus poses a significant global health threat as the source of increasingly deleterious dengue fever, dengue hemorrhagic fever, and dengue shock syndrome. As no specific antiviral treatment exists for dengue infection, considerable effort is being applied to discover therapies and drugs for maintenance and prevention of these afflictions. The virus is primarily transmitted by mosquitoes, and infection occurs following viral endocytosis by host cells. Upon entering the cell, viral RNA is translated into a large multisubunit polyprotein which is post-translationally cleaved into mature, structural and nonstructural (NS) proteins. The viral genome encodes the enzyme to carry out cleavage of the large polyprotein, specifically the NS2B-NS3pro cofactor-protease complex—a target of high interest for drug design. One class of recently discovered NS2B-NS3pro inhibitors is the substrate-based trifluoromethyl ketone containing peptides. These compounds interact covalently with the active site Ser135 via a hemiketal adduct. A detailed picture of the intermolecular protease/inhibitor interactions of the hemiketal adduct is crucial for rational drug design. We demonstrate, through the use of protein- and ligand-detected solution-state ¹⁹F and ¹H NMR methods, an unanticipated multibinding mode behavior of a representative of this class of inhibitors to dengue NS2B-NS3pro. Our results illustrate the highly dynamic nature of both the covalently bound ligand and protease protein structure, and the need to consider these dynamics when designing future inhibitors in this class.

中文翻译：

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抑制剂结合登革热NS2B-NS3pro揭示了多种动态结合模式

登革热病毒作为日益严重的登革热，登革出血热和登革热休克综合症的来源，对全球健康构成重大威胁。由于不存在针对登革热感染的特异性抗病毒治疗，因此人们花费了相当大的精力来发现用于维持和预防这些疾病的疗法和药物。该病毒主要通过蚊子传播，感染在宿主细胞病毒内吞后发生。进入细胞后，病毒RNA被翻译成一个大的多亚基多蛋白，该蛋白在翻译后被切割成成熟的，结构的和非结构的（NS）蛋白。病毒基因组编码酶以切割大的多蛋白，特别是NS2B-NS3pro辅因子-蛋白酶复合物，这是药物设计的重要目标。一类最近发现的NS2B-NS3pro抑制剂是基于底物的含三氟甲基酮的肽。这些化合物通过半加合物与活性位点Ser135共价相互作用。半分子加合物的分子间蛋白酶/抑制剂相互作用的详细图片对于合理的药物设计至关重要。我们通过使用蛋白质和配体检测到的溶液状态来证明¹⁹ F和¹ H NMR方法是此类抑制剂代表登革热NS2B-NS3pro的意外的多结合模式行为。我们的结果说明了共价结合的配体和蛋白酶蛋白结构的高度动态性质，以及在设计此类中的未来抑制剂时需要考虑这些动态。