Gold Nanoparticle-Based Photo-Cross-Linking Strategy for Cellular Target Identification of Supercomplex Molecular Systems

Abstract

Cellular target identification plays an essential role in innovative drug development and pharmacological mechanism elucidation. However, very few practical experimental methodologies have been developed for identifying target proteins for supercomplex molecular systems such as biologically active phytochemicals or pharmaceutical compositions. To overcome this limitation, we synthesized gold nanoparticles (AuNPs) as solid scaffolds, which were bound with 4,4′-dihydroxybenzophenone (DHBP) as a photo-cross-linking group on the surface. Then, DHBP-modified AuNPs cross-linked various organic compounds from phytochemicals under ultraviolet radiation via carbene reactions, H–C bond insertion, for catalytic C–C bond formation. We next used the phytochemical-cross-linked AuNPs (phytoAuNPs) to pull down potential binding proteins from brain tissue lysate and identified 13 neuroprotective targets by mass spectrometry analysis. As an exemplary study, we selected Hsp60 as a crucial cellular target to further screen 14 target-binding compounds from phytochemicals through surface plasmon resonance (SPR) analysis, followed by Hsp60 activity detection and neuroprotective effect assay in cells. Collectively, this gold nanoparticle-based photo-cross-linking strategy can serve as a useful platform for discovering novel cellular targets for supercomplex molecular systems and help to explore pharmacological mechanisms and active substances.

Antimicrobial Potential of Hippocratea indica Acetone Leaf Fractions against Salmonella Typhi: An in vitro and in silico Study

“…The more recent improvement in accessibility of plant natural products is due to enhanced compatibility with high throughput screening (HTS) and advances in lead optimization, compound isolation and identi cation [Ongpipattanakul et al, 2022;Wang et al, 2021;Yao et al, 2022]. The antimicrobial activities of medicinal plants are a function of their phytochemical constituents, therefore the samples were subjected to the characterization of the most active fraction using GC-MS.…”