Supramolecular complex of cytochrome c with lariat ether: solubilization, redox behavior and catalytic activity of cytochrome c in methanol.
A variety of lariat ethers were employed to solubilize water-soluble cytochrome c in methanol, in which alcohol, ether, ester, amine, and amide functionalities were attached as cation-ligating side arms to 18-crown-6, 15-crown-5, and 12-crown-4 rings. Among these lariat ethers, the alcohol-armed 18-crown-6 derivative offered the highest solubilization efficiency for cytochrome c via supramolecular complexation. The resulting cytochrome c-lariat ether complexes were electrochemically and spectroscopically characterized and confirmed to have redox-active heme structures of 6-coordinate low-spin population in methanol. Some of them catalyzed the oxidation of pinacyanol chloride with hydrogen peroxide in methanol and exhibited higher activities than unmodified cytochrome c and its poly(ethylene glycolated) derivative. Since the supramolecular complexation between lariat ether and cytochrome c includes extremely simple procedures, it provides a facile preparation method of effective biocatalysts working in organic solvents from metalloproteins.
Yamada
T
T
Departments of Chemistry and Material Science, Graduate School of Science, Osaka City University, Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan.
Shinoda
S
S
Kikawa
K
K
Ichimura
A
A
Teraoka
J
J
Takui
T
T
Tsukube
H
H
D002232:Carbocyanines / Q000737:chemistry; D002384:Catalysis; D003574:Cytochrome c Group / Q000737:chemistry* / Q000378:metabolism; D004563:Electrochemistry; D004987:Ethers / Q000737:chemistry*; D000432:Methanol / Q000737:chemistry*; D010084:Oxidation-Reduction; D012995:Solubility; D013057:Spectrum Analysis
D002232:Carbocyanines; D003574:Cytochrome c Group; D004987:Ethers; C019071:quinaldine blue; D000432:Methanol