Multi-Ligand-Binding Flavoprotein Dodecin as a Key Element for Reversible Surface Modification in Nano-biotechnology

Area of Science:

• Biotechnology
• Materials Science
• Biochemistry

Background:

• Protein-DNA nanostructures offer versatile platforms for molecular assembly.
• Controlling protein-ligand interactions on surfaces is crucial for biointerface development.

Purpose of the Study:

• To introduce and characterize multiple (re)programming of protein-DNA nanostructures on a single flavin-DNA surface.
• To investigate the binding dynamics of dodecin protein with flavin-terminated DNA monolayers.

Main Methods:

• Systematic study of binding affinity using surface plasmon resonance (SPR) and quartz crystal microbalance with dissipation (QCM-D).
• Surface plasmon fluorescence spectroscopy (SPFS) and dynamic atomic force microscopy (AFM) force spectroscopy were employed.
• Analysis of binding and unbinding rate constants (kon, koff) and dissociation constant (Kd).

Main Results:

• Dodecin forms stable monolayers on flavin-DNA surfaces via multivalent interactions, despite weak individual bonds.
• Stable sandwich-type arrays were formed with bi- or multivalent flavin ligands.
• The dodecin-flavin complex is reversibly disassembled by flavin reduction, enabling alternating ligand binding and release.

Conclusions:

• Demonstrated a versatile concept for reprogrammable functional biointerfaces using dodecin protein.
• The system allows for controlled, reversible assembly and disassembly of protein-DNA nanostructures triggered by redox stimuli.
• This work enables the creation of dynamic and adaptable molecular architectures on surfaces.