Molecular engineering of avidin and hydrophobin for functional self-assembling interfaces

• Published in: Colloids and surfaces, B, Biointerfaces B, Biointerfaces, 2014-08, Vol.120, p.102-109
• Main Authors: Kurppa, Katri, Hytönen, Vesa P., Nakari-Setälä, Tiina, Kulomaa, Markku S., Linder, Markus B.
• Format: Article
• Language: English
• Subjects: Adhesion; Adsorption; Amino Acid Sequence; Animals; Avidin; Avidin - chemistry; Avidin - metabolism; Biofunctional surface; Blotting, Western; Chickens; Electrophoresis, Polyacrylamide Gel; Fungal Proteins - chemistry; Fungal Proteins - metabolism; Hydrophobin; Hypocrea jecorina; Molecular Sequence Data; Nanomaterial; Nanostructure; Partitioning; Protein engineering; Protein Engineering - methods; Proteins; Quartz Crystal Microbalance Techniques; Recombinant Fusion Proteins - chemistry; Recombinant Fusion Proteins - metabolism; Self assembly; Surface chemistry; Trichoderma reesei
• ISSN: 0927-7765; 1873-4367
• DOI: 10.1016/j.colsurfb.2014.05.010

•Design of fusion proteins combining interfacial activity and biotin-binding capability.•Using structural design to efficiently produce fusions of multimerizing proteins.•Demonstration of applicability for interfacial modifications by self-assembly.•Engineered interface ensures controlled binding of biotinylated molecule. Control over the functionality of interfaces through biomolecular engineering is a central tool for nanoscale technology as well as many current applications of biology. In this work we designed fusion proteins that combined the surface adhesion and interfacial activity of a hydrophobin–protein together with the high affinity biotin-binding capability of an avidin–protein. We found that an overall architecture that was based on a circularly permuted version of avidin, dual-chain avidin, and hydrophobin gave a highly functional combination. The protein was produced in the filamentous fungus Trichoderma reesei and was efficiently purified using an aqueous two-phase partitioning procedure. The surface adhesive properties were widely different compared to wild-type avidin. Functional characterization showed that the protein assembled on hydrophobic surfaces as a thin layer even at very low concentrations and efficiently bound a biotinylated compound. The work shows how the challenge of creating a fusion protein with proteins that form multimers can be solved by structural design and how protein self-assembly can be used to efficiently functionalize interfaces.