The problem of the stability globular proteins

Area of Science:

• Biochemistry
• Thermodynamics
• Structural Biology

Background:

• Protein stability is crucial for protein function, turnover, and structural integrity.
• Understanding the thermodynamic principles governing protein stability is essential.

Purpose of the Study:

• To provide a comprehensive survey of protein stability.
• To discuss various methods for measuring protein stability and their implications.
• To compile and discuss data on Gibbs energy change in protein unfolding.

Main Methods:

• Determination of Gibbs energy change in protein unfolding using methods such as denaturants, protonation, heat, scanning calorimetry, and hydrogen exchange.
• Analysis of implications including reversibility, completeness of unfolding, and the two-state assumption.
• Compilation and discussion of existing data on Gibbs energy change in protein unfolding.

Main Results:

• Data compilation shows Gibbs energy change in unfolding for most proteins ranges between 25 and 60 kJ mol-1.
• Discussion of data in relation to protein functioning, turnover, and structural properties.
• Proposal of phase diagrams for a more comprehensive thermodynamic treatment of proteins.

Conclusions:

• Various factors contribute to protein stability, including proteolytic fragments, amino acid replacements, cross-links, prosthetic groups, and ions.
• The study emphasizes the thermodynamic principles underlying protein stability.
• A deeper understanding of protein stability aids in predicting and manipulating protein behavior.