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Updated: Aug 16, 2026
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High-Pressure NMR Experiments for Detecting Protein Low-Lying Conformational States
Published on: June 29, 2021
Compressibility changes accompanying conformational transitions of apomyoglobin
Nicolas Taulier1, Irina V Beletskaya, Tigran V Chalikian
1Department of Pharmaceutical Sciences, Leslie Dan Facultyof Pharmacy, University of Toronto, 19 Russell Street, Toronto, Ontario M5S 2S2, Canada.
Biopolymers
|August 16, 2005
Summary
High-precision measurements reveal distinct differences in apomyoglobin
Area of Science:
- Biophysical Chemistry
- Protein Folding Dynamics
- Thermodynamics of Biomolecules
Background:
- Apomyoglobin undergoes conformational changes.
- Molten globule states are key intermediates in protein folding.
- Acid and salt conditions induce distinct apomyoglobin conformations.
Purpose of the Study:
- To characterize native, molten globule, and unfolded states of apomyoglobin.
- To quantify adiabatic compressibility changes during protein transitions.
- To differentiate between various molten globule states.
Main Methods:
- High-precision density measurements.
- Ultrasonic velocity measurements.
- Densitometric and acoustic data analysis.
Main Results:
- Acid/salt-induced transitions show varying adiabatic compressibility changes.
- N-to-MG(pH4) transitions decrease compressibility.
- N-to-MG(pH2) transitions show mixed compressibility changes, indicating distinct unfolding degrees.
Conclusions:
- Adiabatic compressibility data quantitatively characterize apomyoglobin molten globule states.
- Significant disparities exist between different molten globule forms.
- Volumetric insights aid understanding of apomyoglobin folding pathways and kinetics.
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