Alternatively for mipdatabase quick searches go here

Custom Search

Abstract: A strategy for design of bioimprinted proteins with glutathione peroxidase (GPX) activity has been proposed. The proteins imprinted with a glutathione derivative were converted into selenium-containing proteins by chemical modifying the reactive hydroxyl groups of serines followed by sodium hydrogen selenide displacement. These selenium-containing proteins exhibited remarkable GPX activities and the GPX activities of reduction of H2O2 by glutathione (GSH) were found to be 101-817 U mumol(- 1), which approaches the activity of a selenium-containing catalytic antibody elicited by a hapten similar to our template. The steady state kinetic study for imprinted protein catalysis revealed Michaelis-Menten kinetics for both H2O2 and GSH, e.g. the pesudo-first-order rate constant k(cat) (H2O2) and the apparent Michaelis constant K-m (H2O2) at 1 mM GSH were calculated to be 784 min(-1) and 1.24 x 10(-3) M, respectively, and the apparent second-order rate constant k(cat) (H2O2)/K-m (H2O2) was determined to be 6.33 x 10(5) (M min)(-1). The kinetics and the template inhibition showed that the strategy might be a remarkably efficient one for generating artificial enzyme with GPX activity. (C) 2003 Elsevier B.V. All rights reserved