Circular dichroism (CD) spectroscopy is a widely used technique to characterize the
secondary structure composition of proteins. We have developed the Beta Structure
Selection (BeStSel) method (PNAS, 112, E3095), which solves the main problem of protein
CD spectroscopy—namely, the spectral variability of β-structures. The BeStSel web
server utilizes this method to provide tools to the community for CD spectrum analysis.
BeStSel uniquely provides information on eight secondary structure components, including
parallel β-structure and antiparallel β-sheets with three different twist groups.
It outperforms all available methods in accuracy and information content, and is also
able to predict protein folds down to the topology/homology level of the CATH classification.
The algorithm has been further developed, and the accuracy of the estimation of the
secondary structure elements is improved by 0.7% as an average on the reference dataset.
A new module of the web server calculates protein stability from the thermal denaturation
profile followed by CD. Secondary structure calculations of uploaded PDB and mmcif
files support the experimental verification of MD simulations and AlphaFold models
by CD spectroscopy. Well-proven modules for disorder–order classification and extinction
coefficient calculation continue to work. The BeStSel server is freely accessible
at https://bestsel.elte.hu.
