Inside-out: Antibody-binding reveals potential folding hinge-points within the SARS-CoV-2 replication co-factor nsp9

Research output: Contribution to journalArticleResearchpeer-review

1 Citation (Scopus)


Nsp9 is a conserved accessory component of the coronaviral replication and transcription complex. It is the predominant substrate of nsp12's nucleotidylation activity while also serving to recruit proteins required for viral 5'-capping. Anti-nsp9 specific nanobodies have been isolated previously. We confirm that their binding mode is centred upon Trp-53 within SARS-CoV-2 nsp9. Antibody binding at this site surprisingly results in large-scale changes to the overall topology of this coronaviral unique fold. We further characterise the antibody-induced structural dynamism within nsp9, identifying a number of potentially flexible regions. A large expansion of the cavity between the s2-s3 and s4-s5 loops is particularly noteworthy. As is the potential for large-scale movements in the C-terminal GxxxG helix.

Original languageEnglish
Article numbere0283194
Number of pages13
JournalPLoS ONE
Issue number4
Publication statusPublished - 10 Apr 2023

Cite this