Artificial Trinuclear Metallopeptidase Synthesized by Cross-Linkage of a Molecular Bowl with a Polystyrene Derivative

Abstract

A novel methodology is reported for construction of active sites of artificial multinuclear metalloenzymes: transfer of metal-chelating sites confined in a prebuilt cage to a polymeric backbone. Artificial active sites comprising two or three moieties of Cu(II) complex of tris(2-aminoethyl)amine (tren) were prepared by transfer of Cu(II)tren units confined in a molecular bowl (MB) to poly(chloromethylstyrene-co-divinylbenzene) (PCD). By treatment of unreacted chloro groups of the resulting PCD with methoxide and destruction of the MB moieties attached to PCD with acid followed by addition of Cu(II) ion to the exposed tren moieties, catalytic polymers with peptidase activity were obtained. The average number (β) of proximal Cu(II)tren moieties in the active site of the artificial multinuclear metallopeptidase was determined by quantifying the Cu(II) content. Several species of the artificial metallopeptidases with different β contents were prepared and examined for catalytic activity in hydrolysis of vari...