Heme-Protein Active Site Models via Self-Assembly in Water
journal contributionposted on 21.08.2003, 00:00 authored by Roberto Fiammengo, Kamil Wojciechowski, Mercedes Crego-Calama, Peter Timmerman, Alberto Figoli, Matthias Wessling, David N. Reinhoudt
Water-soluble models of heme-protein active sites are obtained via the self-assembly of cationic porphyrins 1 and tetrasulfonato calixarene 2 (K1·2 = 105 M-1). Selective binding of ligands either outside or inside the cavity of assemblies 1·2 via coordination to the zinc center has been observed. Small ligands such as 4-methylpyridine and 1-methylimidazole are encapsulated, while the bulkier caffeine is bound outside. Assemblies Co-1·2, in which the Zn porphyrin moiety has been replaced by a CoII porphyrin, can act as O2 carriers.