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Updated: Jul 8, 2026
12:29
Optimization of Crystal Growth for Neutron Macromolecular Crystallography
Published on: March 13, 2021
Protein phase behavior in aqueous solutions: crystallization, liquid-liquid phase separation, gels, and aggregates
André C Dumetz1, Aaron M Chockla, Eric W Kaler
1Center for Molecular and Engineering Thermodynamics, Department of Chemical Engineering, University of Delaware, Newark, Delaware 19716, USA.
Biophysical Journal
|December 28, 2007
Summary
Protein crystallization aggregates and gels are explained as gas-liquid phase separation. This study provides a theoretical framework for understanding protein phase behavior and aggregation phenomena.
Area of Science:
- Biophysics
- Physical Chemistry
- Protein Science
Background:
- Protein aggregates and gels in crystallization are often poorly characterized.
- Understanding these disordered phases is crucial for controlling protein crystallization.
Purpose of the Study:
- To investigate the physical nature of protein aggregates and gels during salting-out.
- To develop a theoretical framework for protein phase behavior.
Main Methods:
- Studied protein salting-out for six proteins using ammonium sulfate and sodium chloride.
- Investigated protein phase behavior at three different temperatures (4°C, 23°C, 37°C).
- Interpreted experimental results using theoretical phase diagrams for colloidal particles with attractive interactions.
Main Results:
- Protein aggregate formation can be explained by gas-liquid phase separation.
- A second aggregation line, interpreted as the spinodal, was observed for specific proteins.
- Aggregate formation can represent kinetically trapped states or gel phases via intermediate gas-liquid separation.
Conclusions:
- Theoretical models of short-range attractive interactions provide a useful framework for protein phase behavior.
- These models help describe main features of protein aggregation, despite limitations with temperature effects.
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