Enzyme:nanoparticle bioconjugates with two sequential enzymes: stoichiometry and activity of malate dehydrogenase and citrate synthase on Au nanoparticles.

ABSTRACT: We report the synthesis and characterization of bioconjugates in which the enzymes malate dehydrogenase (MDH) and/or citrate synthase (CS) were adsorbed to 30 nm diameter Au nanoparticles. Enzyme:Au stoichiometry and kinetic parameters (specific activity, k(cat), K(M), and activity per particle) were determined for MDH:Au, CS:Au, and three types of dual-activity MDH/CS:Au bioconjugates. For single-activity bioconjugates (MDH:Au and CS:Au), the number of enzyme molecules adsorbed per particle was dependent upon the enzyme concentration in solution, with multilayers forming at high enzyme:Au solution ratios. The specific activity of adsorbed enzyme increased with increasing number adsorbed per particle for CS:Au, but was less sensitive to stoichiometry for MDH:Au. Dual activity bioconjugates

SUBMITTER: Keighron JD 

PROVIDER: S-EPMC3012446 | biostudies-literature | 2010 Dec

REPOSITORIES: biostudies-literature