Institut Charles Sadron News
Titre : Supramolecular hydrogel based on selfassembled peptides - Structure resolution at near-atomic scale by cryo-electron microscopy
Responsable : Jierry Loïc (SYCOMMOR)
Description du projet
The self-assembly of peptides induced by enzymatic action allows the formation of a nanofibrillar network in space and time, which can support the formation of a so-called supramolecular hydrogel.[1] These materials are currently attracting growing interest due to their use in various fields such as protein crystallisation, enzymatic and supramolecular catalysis, the delivery of bioactive substances, tissue engineering and biomaterials.[2] The properties of these materials are mainly based on the ability of peptide nanofibres to interact with their environment: polymers, nanoparticles, proteins, metals, etc. From a fundamental point of view, understanding the mechanisms that govern the formation of these selfassembled structures and establishing the relationships between the structure of these materials and their properties remain a scientific challenge. And for a good reason: the nearatomic scale structure of these peptide nanofibres is difficult to access, which considerably limits their study. In 2024, our group showed that by using 3D cryo-electron microscopy reconstruction approach, it is possible to resolve the nanostructure of a self-assembled tripeptide fibre (Figure 1).[3] We have thus highlighted a triple helix organisation with wide external grooves and internal cohesion ensured by ‘zipper-like’ organisation of the aromatic groups. This preliminary work shows that we are able to access new structural information to better understand the behaviour of this kind of supramolecular hydrogels. The PhD project proposed herein is in line with these investigations and aims to elucidate the mechanism of assembly of catalytic nanofibres. To do this, the synthesis of several heptapeptide analogues, the evaluation of their catalytic properties and the resolution of their structures will be carried out. Due to its multidisciplinary nature, this subject is aimed at candidates with knowledge of chemistry and physical chemistry, as well as a particular interest in using digital tools. [1] C. Vigier Carrière et al., Angew. Chem., Int. Ed. 2018, 57, 1448-1456; C. Muller et al., Adv. Coll. Interf. Sci. 2022, 304,102660. [2] M. C. Manas-Torres et al. Isr. J. Chem. 2022, 62, e202200018. [3] A. Bigo-Simon et al. ACS Nano 2024, 18, 30448–30462.
Informations complémentaires
Fin de l'offre : 06/06/2025
Lien externe : https://edpcp.u-strasbg.fr/
SCHMUTZ_JIERRY_ICS 2025.pdf