ja981723+_si_001.pdf (128.79 kB)

Immobile Artificial Metalloproteinase Containing Both Catalytic and Binding Groups

Download (128.79 kB)
journal contribution
posted on 10.11.1998, 00:00 by Bo-Bin Jang, Kwan-Pyo Lee, Dal-Hee Min, Junghun Suh
Poly(chloromethylstyrene-co-divinylbenzene) (PCD) with 2% cross-linkage is developed as a backbone of immobile artificial enzymes. As the first artificial enzyme built on PCD, an artificial metalloproteinase is prepared by attaching the Cu(II) complex of cyclen as the catalytic center and guanidinium ion as the binding unit. The PCD derivatives prepared were characterized by scanning electron microscopy, IR spectroscopy, elemental analysis, titration of chloromethylphenyl moiety with triethylamine, complexation of p-nitrobenzoate ion to the guanidinium moiety, quantification of the cyclen moieties retaining high affinity for the Cu(II) ion, and determination of log Kf for the Cu(II) binding sites. The proteinase activity was measured with γ-globulin (Gbn) by following cleavage of the two chains of Gbn by electrophoresis. The catalytic activity of the Cu(II) complex of cyclen toward Gbn was enhanced by more than 104 times upon attachment to PCD. Gbn complexed to the PCD derivative containing both Cu(II)-cyclen and guanidinium moieties was cleaved by hydrolysis into many pieces with a half-life as short as 10−30 min at pH 4.5−7 and 4 °C. Kinetic data revealed that guanidinium ions attached to PCD acted as effective binding sites for the protein, contributing considerably to the overall catalytic power of the immobile artificial metalloproteinase.