Fig. 2: Assembly enhanced binding (AEB) effect of Gi-F-CAA.

a The structure of Gi-F-CAA (peptide-porphyrin conjugate decorated with acid-sensitive CAA moieties). b The structure of Gi-F (peptide-porphyrin conjugate with nanoparticle forming ability). The porphyrin parts were shown in sphere-stick mode with the carbon atoms colored in green and the other parts were shown in stick mode with the carbon atoms colored in cyan. c The self-assembly progress of Gi-F. The porphyrin parts were shown in sphere-stick mode with the carbon atoms colored in green and the other parts were shown in stick mode with the carbon atoms colored in cyan. The MD simulations begun from an initial randomly distributed system. d The self-assembled nanoparticle of Gi-F. e The hydrolysis profiles of Gi-F-CAA at pH 7.4 and 6.5 (PBS, 0.01 M) measured by HPLC (n = 3 experimental repeats). Experiment was independently repeated three times with similar results. f CAC values determined by I₃₃₈/I₃₃₅ ratio from pyrene as a function of concentration of Gi-F-CAA and Gi-F. g Particle size change of Gi-F-CAA and Gi-F (40 μM) in PBS (0.01 M, pH 7.4 or 6.5) measured by DLS. h Representative TEM images of Gi-F-CAA in PBS at pH 7.4 for 1 h (n = 3 experimental repeats). Experiment was independently repeated three times with similar results. i The binding mode between self-assembled nanoparticle and the GPX4mu protein. The porphyrin parts were shown in sphere-stick mode with the carbon atoms colored in green and the other parts were shown in stick mode with the carbon atoms colored in cyan. The GPX4mu protein was shown in cartoon mode and colored in magenta. j Key residues between self-assembled nanoparticle and the GPX4mu protein. k Corresponding TEM images of Gi-F-CAA at pH 6.5 incubated with protein GPX4. l Affinity binding curve of Gi-F-CAA and Gi-F with GPX4. n represents the Hill coefficient calculated from Hill plot. m The binding affinity of Gi-F-CAA to GPX4 by Microscale Thermophoresis (MST) ligand binding measurements. K_d: the dissociation constant. n The binding affinity of Gi-F to GPX4 by MST ligand binding measurements. K_d: the dissociation constant. Data were expressed as mean ± SD. Source data are provided as a Source Data file.