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Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes
Published on: November 21, 2017
Thermodynamically controlled supramolecular polymerization of cytochrome b 562
Hiroaki Kitagishi1, Koji Oohora, Takashi Hayashi
1Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.
Abstract:
A hemoprotein-based supramolecular polymer that has a covalently linked heme moiety on the protein surface has been constructed based on interprotein heme-heme pocket interactions of the chemically modified apocytochrome b(562) (1-H63C). The thermodynamic properties of the polymer have been investigated by means of size exclusion chromatography, UV-vis spectroscopy, and circular dichroism spectroscopy. The results indicate that, as with other synthetic systems reported so far, the 1-H63C hemoprotein assembly is thermodynamically controlled in aqueous solution: the degree of polymerization is dependent on the 1-H63C concentration and is modulated by the addition of the end-capping units, native heme, and/or apocytochrome b(562) mutant (apoH63C). These properties suggest a potential use for the hemoprotein self-assembly in preparation of stimuli-responsive functional nanobiomaterials.
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