Inducible auto-phosphorylation regulates a widespread family of nucleotidyltransferase toxins

Arrowsmith, Tom J.; Xu, Xibing; Xu, Shangze; Usher, Ben; Stokes, Peter; Guest, Megan; Bronowska, Agnieszka K.; Genevaux, Pierre; Blower, Tim R.

Abstract

Nucleotidyltransferases (NTases) control diverse physiological processes, including RNA modification, DNA replication and repair, and antibiotic resistance. The Mycobacterium tuberculosis NTase toxin family, MenT, modifies tRNAs to block translation. MenT toxin activity can be stringently regulated by diverse MenA antitoxins. There has been no unifying mechanism linking antitoxicity across MenT homologues. Here we demonstrate through structural, biochemical, biophysical and computational studies that despite lacking kinase motifs, antitoxin MenA1 induces auto-phosphorylation of MenT1 by repositioning the MenT1 phosphoacceptor T39 active site residue towards bound nucleotide. Finally, we expand this predictive model to explain how unrelated antitoxin MenA3 is similarly able to induce auto-phosphorylation of cognate toxin MenT3. Our study reveals a conserved mechanism for the control of tuberculosis toxins, and demonstrates how active site auto-phosphorylation can regulate the activity of widespread NTases.

Citation

Arrowsmith, T. J., Xu, X., Xu, S., Usher, B., Stokes, P., Guest, M., Bronowska, A. K., Genevaux, P., & Blower, T. R. (2024). Inducible auto-phosphorylation regulates a widespread family of nucleotidyltransferase toxins. Nature Communications, 15(1), Article 7719. https://doi.org/10.1038/s41467-024-51934-1

• Journal Article Type: Article
• Acceptance Date: Aug 22, 2024
• Online Publication Date: Sep 4, 2024
• Publication Date: Sep 4, 2024
• Deposit Date: Sep 4, 2024
• Publicly Available Date: Sep 4, 2024
• Journal: Nature Communications
• Electronic ISSN: 2041-1723
• Publisher: Nature Research
• Peer Reviewed: Peer Reviewed
• Volume: 15
• Issue: 1
• Article Number: 7719
• DOI: https://doi.org/10.1038/s41467-024-51934-1
• Public URL: https://durham-repository.worktribe.com/output/2787365