BIOL 239 |
| Solid-supported enzymes are useful because the conjugated enzymes can be easily separated from reaction mixtures, exhibit enhanced stability and increased activity, and can potentially be reused, while not contaminating reaction products. We report a general, covalent method for the bioconjugation of proteins to the surface of composite nanoparticles, consisting of magnetic nanoparticles encapsulated within a co-polymer micelle shell. In particular, ã-Fe2O3 nanoparticles were co-assembled within amphiphilic poly(styrene250-b-acrylic acid13) block-copolymer micelles, and these “magnetomicelles” were functionalized with Cu2+-iminodiacetic acid (IDA). We conjugated a number of His-tagged proteins to these particles, including T4 DNA ligase, T7 RNA polymerase, and GFP. The resulting protein-magnetomicelle bioconjugates are highly stable in aqueous solutions and compatible to biologically relevant reaction conditions. In addition, the bound proteins retain their original biological activity, and the enzyme bioconjugates are readily recovered and recycled multiple times. These magnetomicelle bioconjugates have given us a way to assess protein activity in biologically applicable contexts and further strengthened the idea that nanoparticle surfaces may prove more useful for protein immobilization than traditional bulk substrates.
|
|
Enzymes
4:30 PM-6:30 PM, Wednesday, 13 September 2006 Moscone Center -- Hall D, Poster
Sci-Mix
Division of Biological Chemistry |
