Effect of gold nanoparticle conjugation on the activity and stability of functional proteins.
Immobilization of functional proteins such as enzymes on solid surfaces produces a variety of effects ranging from the reversal and strong inhibition to the enhancement of protein stability and function. Such effects are protein-dependent and are affected by the physical and chemical properties of the surfaces. Functional consequences of protein immobilization on the surface of gold nanoparticles (AuNPs) are protein-dependent and require thorough investigation using suitable functional tests. However, traditional approaches to making control samples, i.e., immobilized protein vs. protein in solution in absence of any nanoparticles do not provide sufficiently identical reaction conditions and complicate interpretation of the results. This report provides advice and methods for preparing AuNP-conjugated preparations generally suitable for studying the effects of immobilization on the activity and stability of different functional proteins. We use bovine catalase to illustrate our approach, but the methods are easily adaptable to any other enzyme or protein. The AuNP-immobilized enzyme showed increased stability at elevated temperatures compared to the same enzyme in solution.
School of Biological Sciences, Royal Holloway, University of London, Egham, Surrey, UK.
Julian
J
Bailes
Sara
S
Gazi
Rositsa
R
Ivanova
Mikhail
M
Soloviev
D000818:Animals; D002374:Catalase / Q000737:chemistry / Q000378:metabolism; D002417:Cattle; D057075:Enzyme Assays; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism; D006046:Gold / Q000737:chemistry*; D006801:Humans; D053768:Metal Nanoparticles / Q000737:chemistry*; D011485:Protein Binding; D055550:Protein Stability; D011506:Proteins / Q000737:chemistry* / Q000378:metabolism*; D013696:Temperature
D004800:Enzymes, Immobilized; D011506:Proteins; D006046:Gold; D002374:Catalase