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FindMod tool

FindMod is a tool that can predict potential protein post-translational modifications (PTM) and find potential single amino acid substitutions in peptides.

The experimentally measured peptide masses are compared with the theoretical peptides calculated from a specified Swiss-Prot/TrEMBL entry or from a user-entered sequence, and mass differences are used to better characterise the protein of interest [Documentation / Mass values and considered PTMs / Reference].

Swiss-Prot/TrEMBL ID or AC or user-entered sequence:

If your protein is not in Swiss-Prot or TrEMBL, please specify (if known) the source of your protein:
Eukaryote or Bacteria or Archaea or Virus ( Phage).

(This information will be used to determine whether certain post-translational modifications are likely to occur in your sequence.)

Enter a list of peptide masses and intensities (optional) that correspond to the specified protein. Enter one mass, space and its intensity per line:
Or upload a file from your computer, from which the peptide masses will be extracted (supported formats):
Check all or unmatching peptides for the following:
potential post-translational modifications (max. within one peptide). Please note that if 3 is selected, then only a subset of modifications will be considered.
single amino acid substitutions.

If you wish to take into account other post-translational modifications than those already predictable by FindMod, you can specify them here:

modification name amino acids
this modification
can be observed on
atom composition
H: 3, O: 1, C: 2, N:  , S: 
H: , O: , C: , N: , S: 
H: , O: , C: , N: , S: 

All peptide masses are
with cysteines treated with:
with acrylamide adducts on cysteines
with methionines oxidized
with tryptophans oxidized
[M+H]+ or [M] or [M-H]-.
average or monoisotopic.

Mass tolerance: ±

Select an enzyme :

Allow for missed cleavage sites (MC).
Display peptides sorted by peptide masses or in chronological order in the protein.

Send the result by e-mail
Your e-mail address:
name of the unknown protein:

To run the search:
To clear all fields: