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Updated: Aug 15, 2026
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Growing Protein Crystals with Distinct Dimensions Using Automated Crystallization Coupled with In Situ Dynamic Light Scattering
Published on: August 14, 2018
Protein crystals and charged surfaces: interactions and heterogeneous nucleation
1Department of Physics, University of Surrey, Guildford, Surrey, United Kingdom. r.sear@surrey.ac.uk
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|October 26, 2005
Summary
Charged protein crystals interact strongly with surfaces. Oppositely charged surfaces attract crystals, acting as nucleants and lowering the energy barrier for protein crystal formation from solution.
Area of Science:
- Biophysics
- Materials Science
- Crystallography
Background:
- Proteins possess inherent charges, typically around 10.
- These charges dictate strong electrostatic interactions with charged surfaces.
Purpose of the Study:
- To calculate the electrostatic contribution to protein crystal interactions with charged surfaces.
- To investigate the potential of charged surfaces as nucleants for protein crystallization.
Main Methods:
- Computational calculation of electrostatic interactions.
- Analysis of free energy changes upon protein crystal contact with surfaces.
Main Results:
- Charged surfaces exhibit repulsive forces with similarly charged protein crystals.
- Oppositely charged surfaces demonstrate attractive forces towards protein crystals.
- Free energy changes can be significant, reaching several kT per protein molecule.
Conclusions:
- Charged surfaces can effectively nucleate protein crystal formation.
- Heterogeneous nucleation is facilitated by lowering the free energy barrier.
- Surface charge engineering offers a strategy for controlling protein crystallization.
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