Laser‐Polarization‐Induced Anisotropy Enhances Protein Crystallization

Abstract Protein crystallization plays a critical role in structural biology and drug development, driving extensive research into its control. We present a novel approach for manipulating protein crystallization by controlling the anisotropy of the high‐concentration domain (HCD) composed of hen egg‐white lysozyme (HEWL) through laser polarization in optical trapping. The anisotropy of the HCD was assessed through fluorescence anisotropy measurements and polarized Raman spectroscopy. The results revealed that linear polarization significantly enhances crystallization efficiency by inducing anisotropy of the HCD and promoting nucleation. In contrast, circular polarization resulted in weak anisotropy with minimal crystallization efficiency. This study highlights the crucial role of protein molecule anisotropy in crystallization under optical trapping conditions, providing a new strategy to optimize laser conditions for various protein molecules and pave the way for the development of innovative crystallization techniques, potentially revolutionizing structural biology and drug discovery efforts.