SARS-Coronavirus-2 Nsp13 Possesses NTPase and RNA Helicase Activities That Can Be Inhibited by Bismuth Salts

Virol Sin. 2020 Jun;35(3):321-329. doi: 10.1007/s12250-020-00242-1. Epub 2020 Jun 4.


The ongoing outbreak of Coronavirus Disease 2019 (COVID-19) has become a global public health emergency. SARS-coronavirus-2 (SARS-CoV-2), the causative pathogen of COVID-19, is a positive-sense single-stranded RNA virus belonging to the family Coronaviridae. For RNA viruses, virus-encoded RNA helicases have long been recognized to play pivotal roles during viral life cycles by facilitating the correct folding and replication of viral RNAs. Here, our studies show that SARS-CoV-2-encoded nonstructural protein 13 (nsp13) possesses the nucleoside triphosphate hydrolase (NTPase) and RNA helicase activities that can hydrolyze all types of NTPs and unwind RNA helices dependently of the presence of NTP, and further characterize the biochemical characteristics of these two enzymatic activities associated with SARS-CoV-2 nsp13. Moreover, we found that some bismuth salts could effectively inhibit both the NTPase and RNA helicase activities of SARS-CoV-2 nsp13 in a dose-dependent manner. Thus, our findings demonstrate the NTPase and helicase activities of SARS-CoV-2 nsp13, which may play an important role in SARS-CoV-2 replication and serve as a target for antivirals.

Keywords: Antiviral target; Helicase; NTPase; Nsp13; SARS-coronavirus-2 (SARS-CoV-2).

MeSH terms

  • Adenosine Triphosphatases / drug effects
  • Adenosine Triphosphatases / metabolism
  • Betacoronavirus / enzymology
  • Betacoronavirus / genetics
  • Betacoronavirus / metabolism*
  • Bismuth / pharmacology*
  • COVID-19
  • Coronavirus Infections / virology
  • Humans
  • Methyltransferases / genetics
  • Methyltransferases / metabolism*
  • Nucleoside-Triphosphatase / drug effects*
  • Nucleoside-Triphosphatase / genetics
  • Nucleoside-Triphosphatase / metabolism
  • Pandemics
  • Pneumonia, Viral / virology
  • RNA Helicases / drug effects*
  • RNA Helicases / genetics
  • RNA Helicases / metabolism
  • Recombinant Proteins
  • SARS-CoV-2
  • Salts / pharmacology*
  • Severe Acute Respiratory Syndrome
  • Viral Nonstructural Proteins / genetics
  • Viral Nonstructural Proteins / metabolism*
  • Virus Replication


  • Recombinant Proteins
  • Salts
  • Viral Nonstructural Proteins
  • nonstructural protein, coronavirus
  • Methyltransferases
  • Nsp13 protein, SARS-CoV
  • Adenosine Triphosphatases
  • Nucleoside-Triphosphatase
  • RNA Helicases
  • Bismuth