Help & Credits

Generation of unfolded ensembles of proteins and calculation of sequence-specific solvent accessibilities in the folded and unfolded states

Welcome to ProtSA. ProtSA will generate, for your protein of interest, an ensemble of unfolded conformations, and will calculate the average solvent-accessible surface area (SASA) of each atom and residue in the ensemble. All you need to provide is the sequence of your protein using the form below. The accessibilities of protein residues in unfolded ensembles are strongly sequence-dependent. Knowing them in each particular case may be useful to understand mutational effects and to improve parameterizations of protein folding energetics.

As a new feature of ProtSA, you can now obtain the PDB files of the unfolded structures generated for your protein.

In addition, if you provide a structural model of your folded protein (a PDB code, or your own file in PDB format), folded SASA and differences between the folded and unfolded SASA, per atom and per residue, will be calculated. Color-coded sequences summarize the results, and the structural model provided is returned with the B-factor column containing the ratio between the residue folded SASA and its unfolded SASA, allowing a straightforward three-dimensional visualization of exposure changes associated to protein folding.

The results will be emailed to the address you provided.

Thank you for using ProtSA. Please, cite Estrada et al. (2009) and Bernadó et al. (2006).

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Submission form

Please, fill in all fields. Only ASCII printable characters are allowed.

max. 200 ASCII characters

1 chain only

greater than 0.0, 1.4 is a usual value

between 1-2000; 2000 suggested