Related Experiment Video
Updated: Jun 11, 2026

High-Resolution Neutron Spectroscopy to Study Picosecond-Nanosecond Dynamics of Proteins and Hydration Water
Published on: April 28, 2022
The dynamical behavior of hydrated glutathione: a model for protein-water interactions
Sara Emanuela Pagnotta1, Silvina Cerveny, Angel Alegría
1Centro de Fisica de Materiales (CSIC-UPV/EHU)-Materials Physics Center MPC, San Sebastián, Spain. sckpagns@ehu.es
Abstract:
The reliability of tripeptide glutathione as an excellent model for protein-water interactions is tested by means of broadband dielectric spectroscopy. Measurements performed on aqueous solutions with different water contents show a surprisingly rich relaxation map that strongly resembles those observed for more complex protein macromolecules. At variance with what is normally observed for solutions of hydrophilic compounds with similar molecular weights, the presence of at least two water-related processes is detected. The faster one is symmetric, has an Arrhenius temperature dependence with an activation energy E(A) = 0.45 +/- 0.05 eV and is attributed to water dipole reorientation. The slower one undergoes a clear dynamical change from a non-Arrhenius to an Arrhenius temperature dependence when crossing the calorimetric glass transition temperature of the solution from high to low values. This last process is proposed to be due to the dynamics of strongly-hydrated glutathione components, such as carboxyl or aminic groups.
Related Concept Videos
Phase II Reactions: Glutathione Conjugation and Mercapturic Acid Formation
Several distinctive characteristics distinguish glutathione conjugation from other phase II...
Protein Folding
Protein Folding
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...
Physiological Pharmacokinetic Models: Assumption with Protein Binding
Globular Proteins
Globular proteins serve many important physiological functions, such as acting as enzymes, cellular messengers, and molecular transporters. These roles often require the proteins to be soluble in the aqueous...
Noncovalent Attractions in Biomolecules
Four types of noncovalent interactions are hydrogen bonds, van der Waals forces, ionic bonds, and hydrophobic interactions.
Hydrogen bonding results from the electrostatic attraction of a hydrogen atom covalently bonded to a strong-electronegative atom like oxygen,...

