6VJK

Streptavidin mutant M88 (N49C/A86C)

Summary for 6VJK

• Entry DOI: 10.2210/pdb6vjk/pdb
• Descriptor: Streptavidin, BIOTIN (3 entities in total)
• Functional Keywords: biotin-binding protein, antimicrobial protein
• Biological source: Streptomyces avidinii
• Total number of polymer chains: 12
• Total formula weight: 160531.66

Authors

Marangoni, J.M.,Wu, S.C.,Fogen, D.,Wong, S.L.,Ng, K.K.S. (deposition date: 2020-01-16, release date: 2020-12-23, Last modification date: 2024-10-30)

Primary citation

Marangoni, J.M.,Wu, S.C.,Fogen, D.,Wong, S.L.,Ng, K.K.S.
Engineering a disulfide-gated switch in streptavidin enables reversible binding without sacrificing binding affinity.
Sci Rep, 10:12483-12483, 2020

PubMed Abstract: Although high affinity binding between streptavidin and biotin is widely exploited, the accompanying low rate of dissociation prevents its use in many applications where rapid ligand release is also required. To combine extremely tight and reversible binding, we have introduced disulfide bonds into opposite sides of a flexible loop critical for biotin binding, creating streptavidin muteins (M88 and M112) with novel disulfide-switchable binding properties. Crystal structures reveal how each disulfide exerts opposing effects on structure and function. Whereas the disulfide in M112 disrupts the closed conformation to increase k, the disulfide in M88 stabilizes the closed conformation, decreasing k 260-fold relative to streptavidin. The simple and efficient reduction of this disulfide increases k 19,000-fold, thus creating a reversible redox-dependent switch with 70-fold faster dissociation kinetics than streptavidin. The facile control of disulfide formation in M88 will enable the development of many new applications requiring high affinity and reversible binding.

PubMed: 32719366
DOI: 10.1038/s41598-020-69357-5

Experimental method

X-RAY DIFFRACTION (1.6 Å)