Seybert A, Ziebuhr J, Siddell S G
Institute of Virology, University of Würzburg, Germany.
J Gen Virol. 1997 Jan;78 ( Pt 1):71-5. doi: 10.1099/0022-1317-78-1-71.
The replication of coronaviruses involves proteolytic processing of the gene 1 translation products, pp1a and pp1ab. One of the key enzymes in this process is predicted to be a virus-encoded 3C-like proteinase. In this report, we describe a bacterial system that has allowed us to express and characterize a recombinant murine coronavirus (MHV-JHM) 3C-like proteinase. The partially purified protein has been shown to exhibit proteolytic activity in trans and mutation analysis has been used to demonstrate the indispensability of Cys-3495 for enzymatic activity. Finally, the effect of class-specific proteinase inhibitors on the trans cleavage activity of the MHV 3C-like proteinase has been used to demonstrate the functional and structural homology of this enzyme to the picornavirus 3C proteinases.
冠状病毒的复制涉及基因1翻译产物pp1a和pp1ab的蛋白水解加工。该过程中的关键酶之一预计是病毒编码的3C样蛋白酶。在本报告中，我们描述了一种细菌系统，该系统使我们能够表达和表征重组鼠冠状病毒（MHV-JHM）3C样蛋白酶。已证明部分纯化的蛋白在反式中表现出蛋白水解活性，并且已使用突变分析来证明Cys-3495对于酶活性的不可或缺性。最后，已使用类别特异性蛋白酶抑制剂对MHV 3C样蛋白酶的反式切割活性的影响来证明该酶与小RNA病毒3C蛋白酶在功能和结构上的同源性。
