Novel Lysine-Rich Delivery Peptides of Plant Origin ERD and Human S100: The Effect of Carboxyfluorescein Conjugation, Influence of Aromatic and Proline Residues, Cellular Internalization, and Penetration Ability

Fanni Sebák; Lilla Borbála Horváth; Dániel Kovács; János Szolomájer; Gábor K Tóth; Ákos Babiczky; Szilvia Bősze; Andrea Bodor

doi:10.1021/acsomega.1c04637

Novel Lysine-Rich Delivery Peptides of Plant Origin ERD and Human S100: The Effect of Carboxyfluorescein Conjugation, Influence of Aromatic and Proline Residues, Cellular Internalization, and Penetration Ability

ACS Omega. 2021 Dec 6;6(50):34470-34484. doi: 10.1021/acsomega.1c04637. eCollection 2021 Dec 21.

Authors

Fanni Sebák^{1

2}, Lilla Borbála Horváth^{3

4

5}, Dániel Kovács^{1

5}, János Szolomájer⁶, Gábor K Tóth⁶, Ákos Babiczky^{7

8}, Szilvia Bősze^{3

4}, Andrea Bodor¹

Affiliations

¹ Institute of Chemistry, ELTE-Eötvös Loránd University, Pázmány Péter sétány 1/a, H-1117 Budapest, Hungary.
² Doctoral School of Pharmaceutical Sciences, Semmelweis University, Üllői út 26, H-1085 Budapest, Hungary.
³ ELKH-ELTE Research Group of Peptide Chemistry, Eötvös Loránd Research Network, Eötvös Loránd University, Pázmány Péter sétány 1/a, H-1117 Budapest, Hungary.
⁴ National Public Health Center, Albert Flórián út 2-6, Budapest H-1097, Hungary.
⁵ Hevesy György PhD School of Chemistry, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/a, H-1117 Budapest, Hungary.
⁶ Department of Medical Chemistry, University of Szeged, Dóm tér 8, H-6720 Szeged, Hungary.
⁷ Institute of Cognitive Neuroscience and Psychology, Research Centre for Natural Sciences, Magyar tudósok körútja 2, H-1117 Budapest, Hungary.
⁸ Doctoral School of Psychology/Cognitive Science, Budapest University of Technology and Economics, Műegyetem rakpart 3, H-1111 Budapest, Hungary.

Abstract

The need for novel drug delivery peptides is an important issue of the modern pharmaceutical research. Here, we test K-rich peptides from plant dehydrin ERD14 (ERD-A, ERD-B, and ERD-C) and the C-terminal CPP-resembling region of S100A4 (S100) using the 5(6)-carboxyfluorescein (Cf) tag at the N-terminus. Via a combined pH-dependent NMR and fluorescence study, we analyze the effect of the Cf conjugation/modification on the structural behavior, separately investigating the (5)-Cf and (6)-Cf forms. Flow cytometry results show that all peptides internalize; however, there is a slight difference between the cellular internalization of (5)- and (6)-Cf-peptides. We indicate the possible importance of residues with an aromatic sidechain and proline. We prove that ERD-A localizes mostly in the cytosol, ERD-B and S100 have partial colocalization with lysosomal staining, and ERD-C mainly localizes within vesicle-like compartments, while the uptake mechanism mainly occurs through energy-dependent paths.