On methods for determining solvent accessible surface area for proteins in their unfolded state

Area of Science:

• Biophysics
• Computational Biology
• Protein Chemistry

Background:

• Numerous methods exist for calculating solvent accessible surface area (SASA) in unfolded proteins.
• The impact of these methods on thermodynamic variable relationships is not well understood.

Purpose of the Study:

• To compare eight distinct methods for estimating unfolded protein SASA.
• To assess the influence of different SASA estimation methods on thermodynamic parameter correlations.

Main Methods:

• Comparative analysis of eight established methods for SASA calculation.
• Statistical assessment of differences in SASA estimates across methods.
• Evaluation of the correlation between SASA and thermodynamic variables for each method.

Main Results:

• Significant differences in unfolded SASA estimates were observed for most method pairs.
• Four pairs of methods yielded statistically similar unfolded SASA estimates.
• No significant impact of the chosen SASA estimation method was found on the relationship between SASA and thermodynamic parameters.

Conclusions:

• The Gong and Rose transition midpoint method is recommended for SASA computation.
• This method offers computational efficiency, a strong physical basis, and reliable correlations with thermodynamic parameters.