TET peptidases: mode of action and industrial valorization

Principal Investigator: Bruno Franzetti

Group members involved: Joaquin Atalah, Anna Bonardel, Charlotte Raybaud, Mylene Ferruit, Eric Girard and B. Franzetti

Extremophilic genomes mining for novel TET peptidases:

A large part of archaeal genomes encodes for proteins assigned as putative peptidases. We have undertaken the characterization of these orphans’ proteins with a focus on those forming large oligomeric complexes. Our goal is to specify the link between proteolysis and environmental adaptation and to identify enzymes of industrial interest. We focus on the M42 TET peptidases that were discovered in the group using native purification of stress-induced proteins in Archaea. TETs are self-compartmentalized metallo-peptidases comprising 12 subunits forming a unique tetrahedral edifice. TET edifices are conserved in all cell types and exists in several version in many archaea.

Mode of action of the half megadalton TET peptidases:

We are combining enzymology with time resolved X-ray crystallography and Cryo-EM studies to elucidate the assembly processes, substrate specificity and modes of action of TET peptidases machines.

Industrial use of TET peptidases:
Our work allowed to discover novel peptidases and to design enzymes cocktails with unprecedented peptide modification properties (3 European patents). We also develop enzyme immobilization methods based on chemical crosslink that allowed to use hyper-robust extremozymes in food processing with an extended life-time and the possibility to re-cycle the enzymes in industrial processes. We are following a business incubation program in order to develop this technology with the support of the technology transfer company Linksium and the support of the “région Auvergne Rhône Alpes” (Project NutriCLEC). In collaboration with the LEMAR laboratory in Brest, we use this technology to develop functionalized hydrolysates from microalgae for the fish nutrition sector (ANR PCRE project “LIPEP”).

Funding

Collaborations

  • Philippe Soudant, Laboratoire des sciences de l’environnement marin (LEMAR), Brest.
  • Didier Flament, Laboratoire « Biologie et Ecologie des Ecosystemes Marins Profonds » (BEEP), Brest.
  • Simonetta Gribaldo, Institut Pasteur, Paris.
  • Guy Schoehn, Methods and Electron Microscopy Group (MEM), IBS.
  • Sylvain Engilberge, Groupe Synchrotron (GSY), IBS.

Selected Publications

  • Functional and phylogenomic approaches reveal novel types of M42 peptidases with contrasted enzymatic properties in Archaea.
    Emilie Chagny, Najwa Taib, Daphna Fenel, Eric Girard, Simonetta Gribaldo, Didier Flament, Bruno Franzetti. bioRxiv 2025.02.26.640355; doi: https://doi.org/10.1101/2025.02.26.640355
  • Pyrococcus horikoshii TET2 peptidase assembling process and associated functional regulation.
    Journal of Biological Chemistry (2013) 288(31): 22542-22554. Appolaire A, Rosenbaum E, Dura MA, Colombo M, Marty V, Noirclerc Savoye M, Godfroy A, Schoehn G, Girard E, Gabel F and Franzetti B.