Real-Time Observation of Nonclassical Protein Crystallization Kinetics

We present a real-time study of protein crystallization of bovine β-lactoglobulin in the presence of CdCl2 using small-angle X-ray scattering and optical microscopy. From observing the crystallization kinetics, we propose the following multistep crystallization mechanism that is consistent with our data. In the first step, an intermediate phase is formed, followed by the nucleation of crystals within the intermediate phase. During this period,...