Optically Controlled Construction of Three-Dimensional Protein Arrays.

Area of Science:

• Structural biology
• Materials science
• Photochemistry

Background:

• Protein crystallization is crucial for structural biology and nanostructure fabrication.
• Controlling crystallization kinetics and morphology remains a challenge.
• Light-responsive materials offer novel avenues for dynamic control.

Purpose of the Study:

• To develop a light-controlled method for protein crystallization.
• To investigate the use of photo-responsive azobenzene dyes for this purpose.
• To explore the fabrication of protein single crystals and metamaterials.

Main Methods:

• Complexing model proteins with cationic azobenzene dyes.
• Utilizing ultraviolet and visible light to induce and reverse crystallization.
• Controlling azobenzene isomerization kinetics to influence crystal growth.

Main Results:

• Photo-responsive protein crystallites were successfully created.
• Crystalline state could be reversibly switched to a dispersed phase with light.
• Photo-treatment significantly increased crystallinity and enabled crystal formation where none was previously observed.
• Protein single crystals up to ≈50 μm were produced through controlled isomerization kinetics.

Conclusions:

• Light-actuated control over protein crystallization is feasible using azobenzene dyes.
• This technique offers a dynamic and reversible method for fabricating ordered protein structures.
• The approach has potential applications in metamaterial fabrication and studying optically controlled crystallization processes.