Isoelectric Point Calculator 2.0
Prediction of isoelectric point and pKa dissociation constants using deep learning

Isoelectric point, the pH at which a particular molecule carries no net electrical charge, is a critical parameter for many analytical biochemistry and proteomics techniques, especially for 2D gel electrophoresis (2D-PAGE), capillary isoelectric focusing (cIEF), X-ray crystallography and liquid chromatography–mass spectrometry (LC-MS)

Below is the text area where you can paste the amino acid sequence of the analyzed protein (peptide) or multiple sequences in fasta format

  • Input should be ONE sequence in plain text or MULTIPLE sequences in FASTA format
  • The total amino acids limit is set up to max. 75,000 amino acids or 1250 peptides * max. 50 aa, or 25 proteins * max. 3000 aa
    (what less i.e. only 25 proteins are processed, even if they are (much) shorter than 3000 aa)
  • If the input contains at least one sequence >50 aa, the whole input is considered "protein" and 25 sequence limit is applied
  • Input should be in one letter amino acid code, input can be upper or lower case.
  • All non-amino acid characters will be removed from the sequence.
  • For big datasets split your input into 50k chunks.
Input example: for Ala-Pro-Lys-His-Ala-Tyr peptide, please enter APKHAY
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Reference: Kozlowski LP (2020) Isoelectric Point Calculator 2.0 - prediction of isoelectric point and pKa values using deep learning (submitted).

License: IPC is public domain, for details see license
Contact: Lukasz P. Kozlowski