title: Assembling of engineered IgG-binding protein on gold surface for highly oriented antibody immobilization.
abstract: The B-domain, which is one of IgG-binding domains of staphylococcal protein A, was repeated five times and a cysteine residue was introduced at its C-terminus by a genetic engineering technique. The resulting protein, designated B5C1, retained the same IgG-binding activity as native protein A. The B5C1 was assembled on a gold plate surface by utilizing a strong affinity between thiol of cysteine and a gold surface. IgG-binding activity of B5C1 on a gold surface was much higher than that of physically adsorbed B5, which lacks cysteine residue. Furthermore, antigen-binding activity of immobilized antibody molecules through the use of assembled B5C1 on a gold surface was about 4.3 times higher than that of physically adsorbed antibody molecules. Immobilization of highly oriented antibody molecules was realized with the engineered IgG-binding protein.
authors.affiliation: Department of Biological Information, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Kanno
authors.forename: Y
authors.initials: Y
authors.lastname: Yanagida
authors.forename: T
authors.initials: T
authors.lastname: Haruyama
authors.forename: E
authors.initials: E
authors.lastname: Kobatake
authors.forename: M
authors.initials: M
authors.lastname: Aizawa
mesh_terms: D000906:Antibodies / Q000378:metabolism*; D000941:Antigens / Q000378:metabolism; D003545:Cysteine / Q000235:genetics / Q000378:metabolism; D006046:Gold; D007074:Immunoglobulin G / Q000378:metabolism*; D015202:Protein Engineering / Q000379:methods*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism*; D020449:Repetitive Sequences, Amino Acid; D013205:Staphylococcal Protein A / Q000235:genetics / Q000378:metabolism*
chemical_list: D000906:Antibodies; D000941:Antigens; D007074:Immunoglobulin G; D011994:Recombinant Proteins; D013205:Staphylococcal Protein A; D006046:Gold; D003545:Cysteine