The SARS-CoV-2 genome encodes for approximately 30 proteins. Within the international project COVID19-NMR, we distribute the spectroscopic analysis of the viral proteins and RNA. Here, we report NMR chemical shift assignments for the protein Nsp3b, a domain of Nsp3. The 217-kDa large Nsp3 protein contains multiple structurally independent, yet functionally related domains including the viral papain-like protease and Nsp3b, a macrodomain (MD). In general, the MDs of SARS-CoV and MERS-CoV were suggested to play a key role in viral replication by modulating the immune response of the host. The MDs are structurally conserved. They most likely remove ADP-ribose, a common posttranslational modification, from protein side chains. This de-ADP ribosylating function has potentially evolved to protect the virus from the anti-viral ADP-ribosylation catalyzed by poly-ADP-ribose polymerases (PARPs), which in turn are triggered by pathogen-associated sensing of the host immune system. This renders the SARS-CoV-2 Nsp3b a highly relevant drug target in the viral replication process. We here report the near-complete NMR backbone resonance assignment ( 1 H, 13 C, 15 N) of the putative Nsp3b MD in its apo form and in complex with ADP-ribose. Furthermore, we derive the secondary structure of Nsp3b in solution. In addition, 15 N-relaxation data suggest an ordered, rigid core of the MD structure. These data will provide a basis for NMR investigations targeted at obtaining small-molecule inhibitors interfering with the catalytic activity of Nsp3b.
【저자키워드】 SARS-CoV-2, non-structural protein, macrodomain, Solution NMR-spectroscopy, Protein drugability, COVID19-NMR, 【초록키워드】 immune response, SARS-CoV, Proteins, virus, MERS-CoV, Anti-viral, RNA, Replication, Papain-like protease, Protein, viral replication, SARS-CoV-2 genome, International, drug target, inhibitor, NMR, Analysis, secondary structure, Viral protein, complex, domain, host immune system, apo form, backbone, Modification, ENCODE, polymerase, ADP-ribosylation, catalytic activity, Host, ADP-ribose, independent, PROTECT, conserved, addition, in viral, suggested, triggered, turn, catalyzed, modulating, PARPs, the SARS-CoV-2, 【제목키워드】 backbone, ADP-ribose, form,