Comparison of Sucrose and Trehalose for Protein Stabilization Using Differential Scanning Calorimetry.

Area of Science:

• Biochemistry
• Protein Stabilization
• Carbohydrate Chemistry

Background:

• Trehalose is recognized as a superior stabilizer for proteins and biomolecules in aqueous solutions.
• The precise mechanism behind trehalose's stabilization effect remains incompletely understood, despite various proposed theories.
• Structural similarities exist between trehalose and sucrose, suggesting potential comparable stabilizing properties.

Purpose of the Study:

• To compare the protein stabilization efficacy of trehalose versus sucrose.
• To investigate the influence of temperature and sugar concentration on stabilization.
• To elucidate the role of direct sugar-protein interactions in stabilization.

Main Methods:

• Evaluated the stability of lysozyme and myoglobin in the presence of trehalose and sucrose.
• Determined glass transition temperature (Tg) and denaturation temperature (Tden) at varying temperatures and water contents.
• Assessed the impact of varying sugar-to-protein ratios on protein stability.

Main Results:

• Sucrose-containing samples exhibited higher denaturation temperatures (Tden) than trehalose-containing samples, especially at low water content.
• Sucrose demonstrated a superior stabilizing effect at high temperatures, potentially due to increased direct binding to the protein surface.
• Both sugars increased Tden with higher sugar-to-protein ratios, indicating improved stabilization with increased sugar shell formation.

Conclusions:

• Sucrose can be a more effective protein stabilizer than trehalose under specific conditions, particularly at higher temperatures.
• The mechanism of protein stabilization by sugars is temperature-dependent, influenced by complex interactions between protein, sugar, and water.
• No synergistic stabilization effects were observed when combining trehalose and sucrose.