[Expired] Offre CDD ingénieur·e biochimie Cadarache

Internship position for the expression and purification of an engineered protein for lanthanide and actinides extraction

Type of contract: Temporary Contract (6 months)

Location: DRF/BIAM/IPM

Biosciences and Biotechnology Institute Aix-Marseille
UMR 7265 CNRS, CEA, Aix-Marseille Univ.
Bat 1900, Zone Cité des Energies (CEA-Cadarache, Saint Paul-lez-Durance)

Contact: Catherine BERTHOMIEU (), Tél : 04 42 25 43 84

Collaborations: L2ME, CEA-Marcoule

Starting date: Fev or March 2023. Note that we need some time for administrative issues concerning the application, and apply before January 15th 2023.

The missions of CEA Direction for Atomic Energy and Alternative Energies include the research for a Circular Economy of strategic elements such as lanthanides (rare earth elements) and the decommissioning of its own nuclear sites and research support for the decommissioning of the nuclear site of other operators (Orano, EDF) requiring the decontamination of actinide containing liquids. Recent research on lanthanide dependent methylotrophs revealed a protein named “Lanmodulin” with extraordinary affinity (Kd from 5 to 35 pM) and selectivity (106/1 against Cu) for lanthanides and actinides. In addition, complexation is reversible at pH < 2,51,2, while the protein is stable at this pH. In order to develop applications based on Lanmodulin (LanM) in the scope of the CEA, the research project EXACT (Extraction of lanthanides and ACTinides by way of strong affinity and high selectivity protein containing materials) was initiated.

In this context, an internship position is opened for the expression and purification of an engineered form of Lanmodulin fit for Click Chemistry by bioorthogonal and site-specific functionalization with 12-azidododecanoic acid. To this end, Lanmodulin will be expressed in E. coli in a two batch processes. The first batch aims at optimizing the expression of the Lanmodulin template alone, and the second batch aims at the functionalization of Lanmodulin in-vivo by coexpressing the Lanmodulin template and N-myristoyl transferase3. In a second step, the engineered Lanmodulins will be purified by affinity chromatography from both batches. The correct expression of the desired forms of Lanmodulin, i.e template and modified by the N-myristoyl transferase will be verified using mass spectrometry. Lastly, the grafting of the modified Lanmodulin onto a material by Click Chemistry will be optimized, opening the way towards application.

The internship concerns a pluridisciplinary project with a strong focus on protein biochemistry and at the interface with physical chemistry and material chemistry. The biochemical work will be done at the BIAM/IPM (CEA-Cadarache) and the material chemistry and characterization will be done at the ICSM/L2ME (CEA-Marcoule). The candidate should have a profile of a Biotechnological Engineer or equivalent with some practical experience in the expression and isolation of proteins. Training in material chemistry is a plus. A successful internship could allow the opening of a PhD position in the follow-up.

1. Deblonde, G. J.-P. et al. Selective and Efficient Biomacromolecular Extraction of Rare-Earth Elements using Lanmodulin. Inorganic Chemistry 59, 11855–11867 (2020).
2. Mattocks, J. A., Cotruvo, J. A. & Deblonde, G. J.-P. Engineering lanmodulin’s selectivity for actinides over lanthanides by controlling solvent coordination and second-sphere interactions. Chem. Sci. 13, 6054–6066 (2022).
3. Kulkarni, C., Lo, M., Fraseur, J. G., Tirrell, D. A. & Kinzer-Ursem, T. L. Bioorthogonal Chemoenzymatic Functionalization of Calmodulin for Bioconjugation Applications. Bioconjugate Chemistry 26, 2153–2160 (2015).