Crystal structure of an inhibitor complex of the 3C proteinase from hepatitis a virus (HAV) and implications for the polyprotein processing in HAV
Crystal structure of an inhibitor complex of the 3C proteinase from hepatitis a virus (HAV) and implications for the polyprotein processing in HAV
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DOI：
10.1006/viro.1999.9968
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发表时间：
1999-12-05
期刊：
影响因子：
3.7
通讯作者：
James, MNG
中科院分区：
文献类型：
--
作者：
Bergmann, EM;Cherney, MM;James, MNG
病毒多蛋白的蛋白水解过程是甲型肝炎病毒 (HAV) 生命周期中的一个重要步骤，就像在所有正链单链 RNA 病毒或动物中一样。在 HAV 中，3C 蛋白酶是参与多蛋白加工的唯一蛋白水解活性。 3C 蛋白酶对切割位点的特异性识别取决于切割位点的氨基酸序列。 HAV 3C 蛋白酶和二肽抑制剂复合物的结构已通过 X 射线晶体学确定。 HAV 3C 双突变体（C24S、F82A）可被特异性抑制剂碘乙酰缬氨酰苯丙氨酰酰胺抑制。所得复合物具有共价连接至酶的亲核Cys 172 的S-γ原子的乙酰基-Val-Phe-酰胺基团。发现HAV 3C（C24S，F82A）乙酰基-Val-Phe-酰胺复合物的晶体是单斜晶系，空间群P2（1），不对称单元中有4个分子，衍射分辨率为1.9埃。最终的精制结构由 4 分子 HAV 3C (C24S,F82A) 乙酰-val-Phe-酰胺、1 分子 DMSO、1 分子甘油和 514 个水分子组成。不对称单元中的四个分子之间存在相当大的构象差异。对于 15.0 至 1.9 埃分辨率之间的所有观察到的反射，最终的 R 因子为 20.4%，相应的 R 树为 29.8%。二肽抑制剂与蛋白酶的 S-1' 和 S-2' 特异性亚位点结合。晶体结构表明，HAV 3C 蛋白酶具有明确的 S-2' 特异性口袋，并表明 P-2' 残基可能是 HAV 多蛋白加工过程中初级切割位点选择的重要决定因素。 (C) 1999 年学术出版社。
The proteolytic processing of the viral polyprotein is an essential step during the life cycle of hepatitis A virus (HAV), as it is in all positive-sense, single-stranded RNA Viruses or animals. In HAV the 3C proteinase is the only proteolytic activity involved in the polyprotein processing. The specific recognition of the cleavage sites by the 3C proteinase depends on the amino acid sequence of the cleavage site. The structure of the complex of the HAV 3C proteinase and a dipeptide inhibitor has been determined by X-ray crystallography. The double-mutant of HAV 3C (C24S, F82A) was inhibited with the specific inhibitor iodoacetyl-valyl-phenylalanyl-amide. The resulting complex had an acetyl-Val-Phe-amide group covalently attached to the S-gamma atom of the nucleophilic Cys 172 of the enzyme. Crystals of the complex of HAV 3C (C24S, F82A) acetyl-Val-Phe-amide were found to be monoclinic, space group P2(1), having 4 molecules in the asymmetric unit and diffracting to 1.9-Angstrom resolution. The final refined structure consists of 4 molecules of HAV 3C (C24S,F82A) acetyl-val-Phe-amide, 1 molecule of DMSO, 1 molecule of glycerol, and 514 water molecules. There are considerable conformational differences among the four molecules in the asymmetric unit. The final R-factor is 20.4% for all observed reflections between 15.0- and 1.9-Angstrom resolution and the corresponding R-tree is 29.8%. The dipeptide inhibitor is bound to the S-1' and S-2' specificity subsites of the proteinase. The crystal structure reveals that the HAV 3C proteinase possesses a well-defined S-2' specificity pocket and suggests that the P-2' residue could be an important determinant for the selection of the primary cleavage site during the polyprotein processing in HAV. (C) 1999 Academic Press.