ExPASy Logo 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].


Upload a file, one sample per line, tab-delimited:
Print a maximum of consecutive/alternative predictions per peptide.
Predict a maximum of simultaneous PTMs per peptide. Please note that this will slow down and drastically increase the number of predictions. If you select 3, only selected modifications will be predicted.

Include single amino acid substitutions.

Show only matches confirmed by rules.
Show only matches not confirmed by rules, matched by mass only.
Show all.

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