期刊
JOURNAL OF MOLECULAR BIOLOGY
卷 387, 期 5, 页码 1137-1152出版社
ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD
DOI: 10.1016/j.jmb.2009.02.044
关键词
astrovirus; serine protease; polyprotein; antiviral; catalytic triad
资金
- European Community [511960]
- FIRB
- Italian Ministry of University and Research
Astroviruses are single-stranded RNA viruses with a replication strategy based on the proteolytic processing of a polyprotein precursor and subsequent release of the viral enzymes of replication. So far, the catalytic properties of the astrovirus protease as well as its structure have remained uncharacterized. In this study, the three-dimensional crystal structure of the predicted protease of human pathogenic astrovirus has been solved to 2.0 angstrom resolution. The protein displays the typical properties of trypsin-like enzymes but also several characteristic features: (i) a catalytic Asp-His-Ser triad in which the aspartate side chain is oriented away from the histidine, being replaced by a water molecule; (ii) a non-common conformation and composition of the SI pocket; and (iii) the lack of the typical surface beta-ribbons together with a featureless shape of the substrate-binding site. Hydrolytic activity assays indicate that the S1 pocket recognises Glu and Asp side chains specifically, which, therefore, are predicted to occupy the P1 position on the substrate cleavage site. The positive electrostatic potential featured by the S1 region underlies this specificity. The comparative structural analysis highlights the peculiarity of the astrovirus protease, and differentiates it from the human and viral serine proteases. (C) 2009 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据