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The spike glycoprotein of the new coronavirus 2019-nCoV contains a furin-like cleavage site absent in CoV of the same clade

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Abstract

In 2019, a new coronavirus (2019-nCoV) infecting Humans has emerged in Wuhan, China. Its genome has been sequenced and the genomic information promptly released. Despite a high similarity with the genome sequence of SARS-CoV and SARS-like CoVs, we identified a peculiar furin-like cleavage site in the Spike protein of the 2019-nCoV, lacking in the other SARS-like CoVs. In this article, we discuss the possible functional consequences of this cleavage site in the viral cycle, pathogenicity and its potential implication in the development of antivirals.
... SARS-CoV-2 causes severe coronavirus disease 2019 (COVID- 19), which has been the leading global pandemic since outbreaks began at the end of 2019. Unlike the S-protein of SARS-CoV-1, the S-protein of SARS-CoV-2 has a polybasic sequence domain (Arg-Arg-Ala-Arg) (the C-end rule) at the S1-S2 boundary that facilitates cleavage by furin (10), an enzyme convertase that catalyzes conversion of a substance to its active state. Thus, SARS-CoV-2 can easily enter host cells with the aid of NRP1, promoting its infectivity and tropism (11). ...
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