Systematic Proteome Research and Bioanalytics, Institute for Experimental Medicine, Christian-Albrechts-Universität zu Kiel, Kiel, 24105, Germany.
Institute of Biochemistry, University of Luebeck, Luebeck, 23562, Germany.
Proteomics. 2021 Jan;21(2):e2000246. doi: 10.1002/pmic.202000246. Epub 2020 Nov 17.
The genome of coronaviruses, including SARS-CoV-2, encodes for two proteases, a papain like (PL ) protease and the so-called main protease (M ), a chymotrypsin-like cysteine protease, also named 3CL or non-structural protein 5 (nsp5). M is activated by autoproteolysis and is the main protease responsible for cutting the viral polyprotein into functional units. Aside from this, it is described that M proteases are also capable of processing host proteins, including those involved in the host innate immune response. To identify substrates of the three main proteases from SARS-CoV, SARS-CoV-2, and hCoV-NL63 coronviruses, an LC-MS based N-terminomics in vitro analysis is performed using recombinantly expressed proteases and lung epithelial and endothelial cell lysates as substrate pools. For SARS-CoV-2 M , 445 cleavage events from more than 300 proteins are identified, while 151 and 331 M derived cleavage events are identified for SARS-CoV and hCoV-NL63, respectively. These data enable to better understand the cleavage site specificity of the viral proteases and will help to identify novel substrates in vivo. All data are available via ProteomeXchange with identifier PXD021406.
冠状病毒的基因组，包括 SARS-CoV-2，编码两种蛋白酶，一种木瓜样（PL）蛋白酶和所谓的主要蛋白酶（M），一种糜蛋白酶样半胱氨酸蛋白酶，也称为 3CL 或非结构蛋白 5（nsp5）。M 通过自身切割激活，是负责将病毒多蛋白切割成功能单位的主要蛋白酶。除此之外，还描述了 M 蛋白酶还能够加工宿主蛋白，包括参与宿主先天免疫反应的蛋白。为了鉴定 SARS-CoV、SARS-CoV-2 和 hCoV-NL63 冠状病毒三种主要蛋白酶的底物，采用基于 LC-MS 的 N 端组学体外分析方法，使用重组表达的蛋白酶和肺上皮和内皮细胞裂解物作为底物池进行分析。对于 SARS-CoV-2 M，从 300 多种蛋白质中鉴定出 445 个切割事件，而 SARS-CoV 和 hCoV-NL63 的 M 衍生切割事件分别鉴定出 151 和 331 个。这些数据有助于更好地了解病毒蛋白酶的切割位点特异性，并有助于在体内鉴定新的底物。所有数据均可通过 ProteomeXchange 标识符 PXD021406 获取。
