Abstract
The surface of ultrasmall gold nanoparticles with an average diameter of 1.55 nm was conjugated with a 14-3-3 protein-binding peptide derived from CRaf. Each particle carries 18 CRaf peptides, leading to an overall stoichiometry of Au(115)Craf(18). The binding to the protein 14-3-3 was probed by isothermal titration calorimetry (ITC) and fluorescence polarization spectroscopy (FP). The dissociation constant (KD) was measured as 5.0 μM by ITC and 0.9 μM by FP, which was close to the affinity of dissolved CRaf to 14-3-3σ. In contrast to dissolved CRaf, which alone did not enter HeLa cells, CRAF-conjugated gold nanoparticles were well taken up by HeLa cells, opening the opportunity to target the protein inside a cell.
| Original language | English |
|---|---|
| Pages (from-to) | 1456-1463 |
| Number of pages | 8 |
| Journal | ChemBioChem |
| Volume | 22 |
| Issue number | 8 |
| Early online date | 4 Dec 2020 |
| DOIs | |
| Publication status | Published - 16 Apr 2021 |
Funding
The authors acknowledge financial support by the Deutsche Forschungsgemeinschaft (DFG) in the framework of the Collaborative Research Center SFB 1093: Supramolecular Chemistry on Proteins. We thank Dr. Torsten Schaller and Dr. Felix Niemeyer for experimental assistance with NMR spectroscopy and Peter Binz for technical support. We thank Dr. Sebastian Kollenda for help with confocal laser scanning microscopy. We thank Kerstin Brauner and Robin Meya for elemental analyses. We thank Chantal Tekath for experimental assistance. We thank Prof. Hemmo Meyer for access to the ITC equipment. Open access funding enabled and organized by Projekt DEAL.
Keywords
- Gold
- nanoparticles
- peptides
- proteins
- supramolecular chemistry