Team
Team manager: Genevaux Pierre
Presentation
The team is using molecular genetics, structural and genome-wide transcriptomic approaches to characterize novel mechanisms involved in bacterial resilience, especially through the activation of stress-responsive toxin-antitoxin systems and molecular chaperone networks.
Models: Bacteria, Mycobacterium tuberculosis, M. smegmatis and E. coli ; Phages, P1, λ, T4-like
Level of analysis: Molecular genetics; biochemistry; Structure; tRNA-seq
Project 1
Toxin-antitoxin (TA) systems are small genetic elements encoding a deleterious toxin and its antitoxin. They are widespread in bacterial and archaeal genomes, and on mobile genetic elements. They are part of the bacterial immune system and have roles in defending bacteria against phage infection, in the maintenance of genomic regions or plasmids, and in some cases, in bacterial virulence and antibiotic persistence. In addition, the highly toxic nature of certain toxins of TA systems has raised the possibility that new antibacterial properties carried by toxins might be used to identify new drug targets or directly as self-poisoning antimicrobials, alone or in combination with standard antibiotherapy.
In the lab, we are currently characterizing the toxic mechanisms of several new TA systems both in Escherichia coli and in the major human pathogen Mycobacterium tuberculosis, as illustrated more recently by discoveries of the tRNA-specific nucleotidyltransferase MenT family and the ribosome-dependent RNase toxin of the TAC toxin-antitoxin-chaperone tripartite system. In addition, we are also developing TA-based biotechnological tool for protein production.
Project 2
Protein folding in the crowded cellular environment relies upon the essential assistance of molecular chaperones, which protect non-native proteins from misfolding and aggregation, off-pathways in protein biogenesis. Molecular chaperones are present in every cell and cellular compartment and are involved in virtually all known cellular processes. Accordingly, their implication in human cancer, neurodegenerative diseases and bacterial virulence has highlighted them as promising new targets for therapy. Molecular chaperones generally act through cycles of binding and release of hydrophobic polypeptide stretches that are often buried in the native form of proteins. Client peptide segments can also be present in native macromolecular complexes and in this case, molecular chaperones can orchestrate the assembly or disassembly of these complexes. In agreement with such properties, bona fide molecular chaperones functions are critical during de novo protein folding, in response to denaturing stresses, for signal transduction pathways and for protein translocation through biological membranes.
In the lab, we are currently studying new molecular chaperones, especially in M. tuberculosis and developing new tools for the directed evolution of molecular chaperones toward difficult proteins in bacteria.
– Guillet V, Bordes P, Bon C, Marcoux J, Gervais V, Sala AJ, Dos Reis S, Slama N, Israel Mares-Mejía, Cirinesi AM, Maveyraud L, Genevaux P*, Mourey L*. 2019. Structural insights into chaperone addiction of toxin-antitoxin systems. Nat. Commun.10:782 https://doi.org/10.1038/s41467-019-08747-4 CNRS-Actu: https://www.insb.cnrs.fr/fr/cnrsinfo/base-structurale-de-laddiction-de-systemes-toxine-antitoxine-un-chaperon-moleculaire
– Freire DM, Gutierrez C, Garza-Garcia A, Grabowska AD, Sala AJ, Ariyachaokun K, Panikova T, Beckham KSH, Colom A, Pogenberg V, Cianci M, Tuukkanen A, Boudehen YM, Peixoto A, Botella L, Svergun DI, Schnappinger D, Schneider TR, Genevaux P, de Carvalho LPS, Wilmanns M, Parret AHA and Neyrolles O. 2019. An NAD+ phosphorylase toxin triggers Mycobacterium tuberculosis cell death. Mol. Cell 73, 1–10 doi.org/10.1016/j.molcel.2019.01.028n CNRS-Actu: http://www.cnrs.fr/fr/tuberculose-tirer-parti-du-suicide-du-bacille
– Ayala S, Genevaux P, Hureau C, Faller P. 2019. (Bio)chemical Strategies To Modulate Amyloid-β Self-Assembly. ACS Chem. Neurosci. 2019 Aug 21;10(8):3366-3374 DOI: 10.1021/acschemneuro.9b00239 (review)
– Akarsu H, Mansour M, Bordes P, Bigot DJ, Genevaux P, Falquet L. 2019. TASmania: a bacterial Toxin-Antitoxin Systems database. PLoS Computational Biology, Apr 25;15(4):e1006946. doi: 10.1371/journal.pcbi.1006946
– Barriot R, Latour J, Castanié-Cornet MP, Fichant G*, Genevaux P*. 2020. J-Domain Proteins in Bacteria and their Viruses. J. Mol. Biol. 16 Apr 2020, DOI: 10.1016/j.jmb.2020.04.014
– Cai Y¥, Usher B¥, Gutierrez C, Tolcan A, Mansour M, Fineran PC, Condon C, Neyrolles O, Genevaux P*, Blower TR*. 2020. A nucleotidyltransferase toxin inhibits growth of Mycobacterium tuberculosis through inactivation of tRNA acceptor stems. Sci. Adv. 29 Jul: Vol. 6, no. 31, eabb6651, DOI: 10.1126/sciadv.abb6651 CNRS-Actu: https://insb.cnrs.fr/fr/cnrsinfo/une-toxine-provoque-la-mort-de-m-tuberculosis-par-un-mecanisme-jusqualors-inconnu
– Texier P, Bordes P*, Nagpal J, Sala AJ, Mansour M, Cirinesi AM, Xu X, Dougan DA*, Genevaux P*. 2021. ClpXP-mediated Degradation of the TAC Antitoxin is Neutralized by the SecB-like Chaperone in Mycobacterium tuberculosis. J. Mol. Biol. Mar 5;433(5):166815. doi: 10.1016/j.jmb.2021.166815.
– Bordes P*, Genevaux P*. 2021. Control of Toxin-Antitoxin Systems by Proteases in Mycobacterium Tuberculosis. Front. Mol. Biosci. 2021 May 17;8:691399. doi: 10.3389/fmolb.2021.691399.
– Fauvet B, Finka A, Castanié-Cornet MP, Cirinesi AM, Genevaux P, Quadroni M, Goloubinoff P. 2021. Bacterial Hsp90 Facilitates the Degradation of Aggregation-Prone Hsp70-Hsp40 Substrates. 2021. Front. Mol. Biosci. 2021 Apr 15;8:653073. doi: 10.3389/fmolb.2021.653073.
– Zhao L, Castanié-Cornet MP, Kumar S, Genevaux P, Hayer-Hartl M, Hartl FU. 2021. Bacterial RF3 senses chaperone function in co-translational folding. Mol. Cell. Jun 2:S1097-2765(21)00400-7. doi: 10.1016/j.molcel.2021.05.016.
– Zuily L, Lahrach N, Fassler R, Genest O, Faller P, Sénèque O, Denis Y, Castanié-Cornet MP, Genevaux P, Jakob U, Reichmann D, Giudici-Orticoni MT, Ilbert M. 2022. Copper Induces Protein Aggregation, a Toxic Process Compensated by Molecular Chaperones. mBio. Apr 26;13(2):e0325121. doi: 10.1128/mbio.03251-21.
– Mansour M¥, Giudice E¥, Xu X, Akarsu H, Bordes P, Guillet V, Bigot DJ, Slama N, D’urso G, Chat S, Redder P, Falquet L, Mourey L, Gillet R*, Genevaux P*. 2022. Substrate recognition and cryo-EM structure of the ribosome-bound TAC toxin of Mycobacterium tuberculosis. Nat Commun. May 12;13(1):2641. doi: 10.1038/s41467-022-30373-w. CNRS-Actu: https://www.insb.cnrs.fr/fr/cnrsinfo/inhibition-de-la-croissance-du-bacille-de-la-tuberculose-par-une-de-ses-toxines
– Xu X¥, Usher B¥, Gutierrez C, Barriot R, Arrowsmith TJ, Han X, Redder P, Neyrolles O, Blower TR*, Genevaux P*. 2023. MenT nucleotidyltransferase toxins extend tRNA acceptor stems and can be inhibited by asymmetrical antitoxin binding. Nat Commun. 14, 4644. https://doi.org/10.1038/s41467-023-40264-3, CNRS-Actu: https://www.insb.cnrs.fr/fr/cnrsinfo/auto-intoxication-du-bacille-de-la-tuberculose-par-une-toxine-ciblant-la-synthese-des
– Arrowsmith TJ, Xu X, Xu S, Usher B, Stokes P, Guest M, Bronowska AK, Genevaux P*, Blower TR*. 2024. Inducible auto-phosphorylation regulates a widespread family of nucleotidyltransferase toxins. Nat Commun. 15, 7719. https://doi.org/10.1038/s41467-024-51934-1
– Marszalek J, et al (+36 authors), 2024, J-domain proteins: From molecular mechanisms to diseases, Cell Stress Chaperones. Vol 29, https://doi.org/10.1016/j.cstres.2023.12.002 (meeting reports).
– Xu X*, Barriot R, Voisin B, Arrowsmith Tj., Usher B, Gutierrez C, Han X, Pagès P, Redder P, Blower Tr, Neyrolles O, Genevaux P*. 2024. Nucleotidyltransferase toxin MenT extends aminoacyl acceptor ends of serine tRNAs to control Mycobacterium tuberculosis growth. Nat Commun 15, 9596 (2024). doi.org/10.1038/s41467-024-53931-w CNRS-Actu: https://www.insb.cnrs.fr/fr/cnrsinfo/tuberculose-des-toxines-pour-de-nouveaux-traitements
Affiliation
