Biomimetic pheomelanin to unravel the electronic, molecular and supramolecular structure of the natural product. Issue 15 (31st March 2023)

• Record Type: Journal Article
• Authors: Cao, Wei; Mao, Haochuan; McCallum, Naneki C.; Zhou, Xuhao; Sun, Hao; Sharpe, Christopher; Korpanty, Joanna; Hu, Ziying; Ni, Qing Zhe; Burkart, Michael D.; Shawkey, Matthew D.; Wasielewski, Michael R.; Gianneschi, Nathan C.
• Is Part Of: Chemical science. Volume 14:Issue 15(2023)
• Page Start: 4183
• Page End: 4192
• Publication Date: 2023-03-31
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/d2sc06418a
• Languages: English
• ISSNs: 2041-6520

Abstract

Abstract : A robust route to synthetic pheomelanin gives insight into the electronic, molecular and supramolecular structure of the natural product, further advancing our understanding of this important subfamily of melanin. Abstract : Herein, we investigate synthetic routes to a close mimic of natural pheomelanin. Three different oxidative polymerization routes were attempted to generate synthetic pheomelanin, each giving rise to structurally dissimilar materials. Among them, the route employing 5-cysteinyl-dihydroxyphenylalanine (5-CD) as a monomer was verified as a close analogue of extracted pheomelanin from humans and birds. The resulting biomimetic and natural pheomelanins were compared via various techniques, including solid-state Nuclear Magnetic Resonance (ssNMR) and Electron Paramagnetic Resonance (EPR). This synthetic pheomelanin closely mimics the structure of natural pheomelanin as determined by parallel characterization of pheomelanin extracted from multiple biological sources. With a good synthetic biomimetic material in hand, we describe cation-π interactions as an important driving force for pheomelanogenesis, further advancing our fundamental understanding of this important biological pigment.