title: Functionalization of thioctic acid-capped gold nanoparticles for specific immobilization of histidine-tagged proteins.
abstract: This paper presents an efficient strategy for the specific immobilization of fully functional proteins onto the surface of nanoparticles. Thioctic acid-derivatized gold clusters are used as a scaffold for further stepwise modification, leading to a cobalt(II)-terminated ligand shell. A histidine tag introduced by genetic engineering into a protein is coordinated to this transition metal ion. The specific immobilization has been demonstrated for the cases of a genetically engineered horseradish peroxidase and ferredoxin-NADP(+) reductase, confirming the attachment of the fully functional proteins to the Co(II)-terminated nanointerface. The absence of nonspecific protein adsorption and the specificity of the binding site have been verified using several analogues of the enzymes without the histidine tag.
authors.affiliation: Instituto de Catálisis y Petroleoquímica, CSIC, C/Marie Curie 2, 28049 Madrid, Spain. jmabad@icp.csic.es
authors.forename: José M
authors.initials: JM
authors.lastname: Abad
authors.forename: Stijn F L
authors.initials: SF
authors.lastname: Mertens
authors.forename: Marcos
authors.initials: M
authors.lastname: Pita
authors.forename: Victor M
authors.initials: VM
authors.lastname: Fernández
authors.forename: David J
authors.initials: DJ
authors.lastname: Schiffrin
mesh_terms: D001665:Binding Sites; D003035:Cobalt / Q000737:chemistry; D004800:Enzymes, Immobilized / Q000737:chemistry*; D005287:Ferredoxin-NADP Reductase / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D006639:Histidine / Q000737:chemistry*; D006735:Horseradish Peroxidase / Q000737:chemistry*; D008024:Ligands; D049329:Nanostructures / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013379:Substrate Specificity; D008063:Thioctic Acid / Q000031:analogs & derivatives* / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D004800:Enzymes, Immobilized; D008024:Ligands; D014867:Water; D003035:Cobalt; D006639:Histidine; D008063:Thioctic Acid; D006046:Gold; D006735:Horseradish Peroxidase; D005287:Ferredoxin-NADP Reductase