Tetrameric Streptavidin Mutein With Reversible Biotin Binding Capability

摘要

The present invention relates to a new streptavidin muteins. This mutein is The muteins are capable of oligomerization to form tetramers, with relatively strong subunit interactions, dissociation constant (KD) for biotin in this mutein in the range of 10−7 to 10−8M, off-rate (koff) for the bound biotin in the streptavidin-biotin complex in the range of 10−4 sec−1, stable enough to allow reuse, and producible producable with reasonable production yield via secretion in a soluble functional state without the requirement of refolding streptavidin via the tedious and expensive denaturation and renaturation processes.