Professor, Dr. Christian P. R. Hackenberger, Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP) & Humboldt Universität zu Berlin

Peptide-conjugates and additives for intracellular protein delivery

Understanding protein function constitutes a central endeavor in the molecular life sciences. This has been fueled by the development of ingenious chemical methods to synthesize or modify functional proteins, which allowed, for instance, to investigate functional consequences of naturally occurring posttranslational protein modifications (PTMs).^[1] Nevertheless, performing such investigations in complex biological environments is severely limited due to the challenges associated with transporting (semi-)synthetic protein materials inside living cells, caused by low delivery efficiency or unwanted intracellular entrapment of protein cargoes.

In this presentation, I will highlight our efforts for the intracellular delivery of protein- and antibody-conjugates. To achieve this, we employ cyclic as well as linear cell-penetrating peptides (CPPs) to enhance the non-endosomal cellular uptake, either as protein conjugates^[2] or in form of cell-surface bound CPP-additives.^[3] Particular aims include the delivery of cell-permeable nanobodies to allow the visualization of intracellular targets, the identification of interaction partners or the modulation of protein targets inside cells to illustrate their potential as next-generation biopharmaceuticals.^[4] Hereby, I will introduce a recently developed photocatalytic method termed DarT-labeling for the intracellular identification of peptide binders.   

References
[1] a) T.W. Muir, S.B.H. Kent, Curr. Opin. Biotechnol. 1993, 4, 420-427; b) S. S. Kulkarni, J. Sayers, B. Premdjee, R. J. Payne, Nat. Rev. Chem. 2018, 2, 0122; c) A.C. Conibear, Nat. Rev. Chem. 2020, 4, 674-695.
[2] a) N. Nischan, H.D. Herce, F. Natale, N. Bohlke, N. Budisa, M.C. Cardoso, C.P.R. Hackenberger, Angew. Chem. Int. Ed. 2015, 54(6), 1950-1953; b) H. Herce, D. Schumacher, F.A. Mann, A. Ludwig, A. Schneider, M. Filies, S. Reinke, C. Cardoso, C.P.R. Hackenberger, Nature Chem. 2017, 9, 762-771.
[3] A.F.L. Schneider, M. Kithil, M.C. Cardoso, M. Lehmann, C.P.R. Hackenberger; Nature Chem. 2021, 13, 530-539.
[4] a) A.F.L. Schneider, L. Benz, M. Lehmann, C.P.R. Hackenberger, Angew. Chem. Int. Ed. 2021, 60(40), 22075-22080; b) V. Arafiles, J. Franke, L. Franz, J. Gómez-González, K. Kemnitz-Hassanin, C.P.R. Hackenberger, J. Am. Chem. Soc. 2023, 145, 24535-24548; c) L. Franz, T. Rubil, A. Balázs, M. Overtus, K. Kemnitz-Hassanin, C. Govaerts, M. A. Mall, C. P. R. Hackenberger, bioRxiv 2024.04.26.591242.