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Crystallizing Membrane Proteins for Structure Determination using Lipidic Mesophases
Published on: November 21, 2010
Conformational fluctuations affect protein alignment in dilute liquid crystal media
Martti Louhivuori1, Renee Otten, Kresten Lindorff-Larsen
1Department of Physical Sciences, Gustaf Hällströmin katu 2, University of Helsinki, Finland.
Journal of the American Chemical Society
|March 30, 2006
Summary
Dilute liquid crystals enable studying biomolecular structures using NMR spectroscopy. Molecular fluctuations influence alignment, emphasizing specific protein conformations and revealing liquidlike molecular surfaces.
Area of Science:
- Biophysics
- Structural Biology
- Nuclear Magnetic Resonance (NMR) Spectroscopy
Background:
- Dilute liquid crystalline media facilitate the alignment of biological macromolecules.
- This alignment is crucial for studying protein and nucleic acid structures using NMR spectroscopy.
Purpose of the Study:
- To investigate the alignment phenomenon in biological macromolecules within liquid crystalline media.
- To understand how molecular fluctuations affect alignment and influence NMR signals.
- To explore the implications for protein structure determination using the weak alignment method.
Main Methods:
- Analysis of residual dipolar coupling (RDC) signals from aligned protein ensembles.
- Inspection of the alignment phenomenon in dilute liquid crystalline media.
- Computational modeling to deduce contributions of different protein conformations.
Main Results:
- Molecular fluctuations significantly impact macromolecular alignment.
- Specific protein conformations are emphasized due to these fluctuations.
- Internal molecular fluctuations are largely uncorrelated with alignment fluctuations, suggesting liquidlike protein surfaces.
- A dynamic bias can affect structure determination from weak alignment data.
Conclusions:
- Protein molecular surfaces exhibit liquidlike dynamics.
- Understanding dynamic effects is essential for accurate protein structure determination using NMR.
- Liquid crystalline media offer powerful tools for probing biomolecular dynamics and structure.
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