title: A fine-tuned composition of protein nanofibrils yields an upgraded functionality of displayed antibody binding domains.
abstract: Elevated performance of instruments and electronic devices is frequently attained through miniaturization of the involved components, which increases the number of functional units in a given volume. Analogously, to conquer the limitations of materials used for the purification of monoclonal antibodies and for the sensitivity of immunoassays, the support for capturing antibodies requires miniaturization. A suitable scaffold for this purpose are cross-β structured protein nanofibrils, as they offer a superior surface area over volume ratio and because manipulation can be implemented genetically. To display the antibody binding Z-domain dimers (ZZ) along the surface of the fibrils and grant maximal accessibility to the functional units, the N-terminal fragments of the fibrillating translation release factor Sup35 or ureidosuccinate transporter Ure2, both from Saccharomyces cerevisae, are simultaneously fibrillated with the chimeric-proteins Sup35-ZZ and ZZ-Ure2, respectively. Optimization of the fibril composition yields a binding capacity of 1.8 mg antibody per mg fibril, which is a binding capacity that is almost 20-fold higher, compared to the commercially available affinity medium gold standard, protein A sepharose. This study lifts the craft of nanofibril functionalization to the next level, and offers a universal framework to improve biomaterials that rely on the display of functional proteins or enzymes.
authors.affiliation: Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Schmuck
authors.affiliation: Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden.
authors.forename: Mats
authors.initials: M
authors.lastname: Sandgren
authors.affiliation: Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden.
authors.forename: Torleif
authors.initials: T
authors.lastname: Härd
mesh_terms: D000911:Antibodies, Monoclonal / Q000302:isolation & purification / Q000378:metabolism*; D005979:Glutathione Peroxidase / Q000378:metabolism*; D010454:Peptide Termination Factors / Q000378:metabolism*; D011328:Prions / Q000378:metabolism*; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*
chemical_list: D000911:Antibodies, Monoclonal; D010454:Peptide Termination Factors; D011328:Prions; C068068:SUP35 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D005979:Glutathione Peroxidase; C067020:URE2 protein, S cerevisiae
keywords: Antibody purification; Functional nanofibrils; Saccharomyces cerevisae; Sup35; Ure2; Z-domain