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Updated: Jul 19, 2026
06:26
Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Thermal transition of core particle is not a two-state process
M Erard1, G de Murcia, A Mazen
1Institut de Biologie Moléculaire et Cellulaire du CNRS, Laboratoire de Biophysique, 67084 Strasbourg Cedex, France.
Biophysical Chemistry
|February 1, 1980
Summary
Core particle thermal transitions are complex, involving unfolding and aggregation, not a simple two-state process. This means thermodynamic parameters cannot be determined using circular dichroism alone.
Area of Science:
- Structural biology
- Biophysics
Background:
- Core particles are fundamental units of chromatin.
- Understanding their stability is crucial for DNA packaging and regulation.
- Previous studies often assumed simple thermal transitions.
Purpose of the Study:
- To investigate the complex thermal transition of isolated core particles.
- To determine if thermodynamic parameters of unfolding can be accurately measured.
- To compare the stability of isolated core particles with those in chromatin.
Main Methods:
- Monitoring thermal transitions using circular dichroism.
- Analyzing thermal denaturation kinetics.
- Comparing isolated core particles with those within chromatin.
Main Results:
- Core particle thermal transition is not a two-state process, but involves unfolding followed by aggregation.
- Static experiments using circular dichroism cannot yield accurate thermodynamic parameters for unfolding.
- Core particle stability is greater within chromatin than in isolation.
Conclusions:
- The complex nature of core particle thermal transitions limits the application of standard thermodynamic analysis.
- Thermal denaturation kinetics offer insights into core particle stability.
- Chromatin structure enhances the stability of core particles.
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