C and N terminal peptide modifications not possible

Issue #1 resolved
created an issue

The Select Modifications and Add Custom Modifications screens do not allow adding N or C terminal modifications, such as TMT or iTRAQ tags. Using -, as in the .cfg file, is not accepted as an amino acid, using [ or ] is accepted when adding a modification, but does not show up in the list of modification to select.

Comments (4)

  1. Lev Levitsky repo owner


    Here's an example that works for me. In the "Add Custom Modification" page, I put in:

    Modification name:  Acetylation
    Modification label: ac
    Mass change or formula: 42.010565
    Amino acids: [

    The modification then shows up in the list and works in the search.
    If something is off in the input, it can happen that errors are silently ignored when adding custom modifications.
    We know it's not very friendly or intuitive at the moment, and we'll work on it.

  2. mglubber reporter

    Hi Lev,

    I just checked, and adding new modifications with the [ or ] as the amino acid only shows up in variable (potential), not fixed, modifications list. For TMT or iTRAQ labelling, fixed would be preferred (because the vast majority of all peptides should be modified)

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