Abstract

In-cell NMR provides insights on biological macromolecules in their native cellular environment at atomic resolution. At CERM , we have developed an approach for expressing and labelling proteins directly in human cells, which is ideally applied to monitor functional processes such as protein folding and maturation, metal binding, chemical modifications, and interactions with ligands or with specific partners.(1) The development of an NMR bioreactor has made possible to study the above processes in real time. The approach provides insights on intracellular ligand binding kinetics and thermodynamics, which are critical to optimize drug penetrance and potency.(2,3) Recently, we have developed 19F in-cell NMR methodologies, which allow protein-observed and ligand-observed screenings on targets that would be otherwise invisible by conventional 1H in-cell NMR .(4) Such approaches hold great potential in the development of more effective drugs towards pharmacologically relevant targets.

(1) Barbieri, L.; Luchinat, E.; Banci, L. Characterization of Proteins by In-Cell NMR Spectroscopy in Cultured Mammalian Cells. Nat. Protoc. 2016, 11 (6), 1101–1111.

(2) Luchinat, E.; Barbieri, L.; Cremonini, M.; Nocentini, A.; Supuran, C. T.; Banci, L. Drug Screening in Human Cells by NMR Spectroscopy Allows the Early Assessment of Drug Potency. Angew. Chem. Int. Ed. Engl. 2020, 59 (16), 6535–6539.

(3) Luchinat, E.; Barbieri, L.; Cremonini, M.; Pennestri, M.; Nocentini, A.; Supuran, C. T.; Banci, L. Determination of Intracellular Protein-Ligand Binding Affinity by Competition Binding in-Cell NMR . Acta Crystallogr. D Struct. Biol. 2021, 77 (Pt 10), 1270–1281.

(4) Pham, L. B. T.; Costantino, A.; Barbieri, L.; Calderone, V.; Luchinat, E.; Banci, L. Direct Expression of Fluorinated Proteins in Human Cells for 19F In-Cell NMR Spectroscopy. J. Am. Chem. Soc. 2023, 145 (2), 1389–1399.