pepKalc is a program that efficiently calculates the electrostatic interactions within (intrinsically) disordered polypeptides and peptides. The program departs from a suggestion by H-X Zhou to model the electrostatics by Debije-Hückel theory, and the polypeptide chain as a Gaussian chain (Zhou HX. Proc Natl Acad Sci U S A. 2002 99(6):3569-74) but uses a hybrid model to consider explicitly strong electrostatics between subsets of charges, while treating the remainder by a mean field model. The program can calculate titration curves, pKa constants and Hill parameters for chains of any length in seconds.


K. Tamiola, R.M. Scheek, P. van der Meulen & F.A.A. Mulder
pepKalc – scalable and comprehensive calculation of electrostatic interactions in random coil polypeptides
. 2018 Jan 22. doi: 10.1093/bioinformatics/bty033
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