Protein crystallization at the air/water interface induced by shearing bulk flow

Area of Science:

• Biophysics
• Materials Science
• Chemical Engineering

Background:

• Two-dimensional (2D) protein crystallization is crucial for structural biology and materials science.
• Achieving ordered 2D protein crystals can be challenging, often requiring specific solution conditions.
• Existing methods may not be sufficient for crystallization under all desired circumstances.

Purpose of the Study:

• To investigate the effect of fluid flow on 2D protein crystallization.
• To identify the specific flow characteristics that promote or accelerate protein crystallization.
• To elucidate the underlying mechanisms by which flow influences crystal formation.

Main Methods:

• Experimental observation of 2D protein crystallization under controlled flow conditions.
• Systematic variation of flow parameters, including shear rate and direction.
• Analysis of crystal formation and morphology in response to applied shear.
• Theoretical considerations of potential mechanisms.

Main Results:

• 2D protein crystallization was observed under flow conditions where it failed in quiescent systems.
• Fluid flow significantly accelerated the crystallization process compared to static conditions.
• Enhanced crystallization directly correlated with large shear forces applied parallel to the interface.
• Specific flow regimes were identified as critical for promoting crystallization.

Conclusions:

• Interfacial shear is a key factor in promoting and accelerating 2D protein crystallization.
• Flow-induced shear can overcome limitations in static crystallization methods.
• Understanding these mechanisms can lead to optimized protocols for protein crystal growth for structural and materials applications.