Supramolecular Complex of Cytochrome c with a Polyanionic β-Cyclodextrin


  • This study was supported by Grants-in-Aid on Scientific Research B (No. 17350074) from the Ministry of Education, Culture, Sports, Science, and Technology, Japan.


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A threesome: An anionic cyclodextrin binds electrostatically with cationic cytochrome c (K=2.3×104M−1, ΔH=9.3 kJ mol−1, ΔS=115 J mol−1 K−1). The cyclodextrin covers the hemin pockets of about two-thirds of the cyt c molecules. This association complex further complexes with a nonionic porphyrin to form a ternary complex in which static fluorescence quenching of the porphyrin by cyt c takes place.