Catalytic Functions of Artifical Enzyme Composed of Simple Vitamin B12 Model and Synthetic Bilayer Membrane

Article abstract of DOI:10.1246/bcsj.64.2744

An artificial enzyme was constructed with a combination of the single-walled vesicle of N,N-dihexadecyl-N^α-<6-(trimethylammonio)hexanoyl>-L-alaninamide bromide (N⁺C5Ala2C16) and a simple vitamin B₁₂ model; (11-hydroximino-4,10-dipropyl-5,9-diazatrideca-4,9-dien-3-one oximato)cobalt, , or cobalt, .Carbon-skeleton rearrangement reactions of alkyl ligands bound to the cobalt complexe were markedly favored in the single-walled vesicle, relative to the reactions in methanol and benzene, under anaerobic photolysis conditions at ordinary temperatures.The cobalt complex incorporated into the intramembrane domain is subjected to significant repression of its molecular motion and to desolvation as confirmed by fluorescene and fluorescence polarization measurements.The 1,2-migration of cyano and carboxylic esters groups involved in the alkyl ligands is plausibly enhanced by such effects.