Lehtonen, Soili I.; Tullila, Antti; Agrawal, Nitin; Kukkurainen, Sampo; Kahkonen, Niklas; Koskinen, Masi; Nevanen, Tarja K.; Johnson, Mark S.; Airenne, Tomi T.; Kulomaa, Markku S.; Riihimaki, Tiina A.; Hytonen, Vesa P.
Artificial Avidin-Based Receptors for a Panel of Small Molecules
ACS CHEMICAL BIOLOGY, 11:211-221, JAN 2016

Proteins with high specificity, affinity, and stability are needed for biomolecular recognition in a plethora of applications. Antibodies are powerful affinity tools, but they may also suffer from limitations such as low stability and high production costs. Avidin and streptavidin provide a promising scaffold for protein engineering, and due to their ultratight binding to D-biotin they are widely used in various biotechnological and biomedical applications. In this study, we demonstrate that the avidin scaffold is suitable for use as a novel receptor for several biologically active small molecules: Artificial, chicken avidin-based proteins, antidins, were generated using a directed evolution method for progesterone, hydrocortisone, testosterone, cholic acid, ketoprofen, and folic acid, all with micromolar to nanomolar affinity and significantly reduced biotin-binding affinity. We also describe the crystal structure of an antidin, sbAvd-2(I117Y), a steroid-binding avidin, which proves that the avidin scaffold can tolerate significant modifications without losing its characteristic tetrameric beta-barrel structure, helping us to further design avidin-based small molecule receptors.


Find full text with Google Scholar.