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FindPept tool

FindPept can identify peptides that result from unspecific cleavage of proteins from their experimental masses, taking into account artefactual chemical modifications, post-translational modifications (PTM) and protease autolytic cleavage. If you wish to take into account only specific cleavage, please use FindMod instead.

The experimentally measured peptide masses are compared with the theoretical peptides calculated from a specified UniProtKB (Swiss-Prot or TrEMBL) entry or from a user-entered sequence. If autolysis is to be taken into account, an enzyme entry must be specified from the drop-down list of enzymes for which the sequence is known. [Documentation / Mass values and considered PTMs / References].

UniProtKB ID or AC or user-entered sequence (you may specify post-translational modifications, as specified in this document):

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):

If you wish to define other post-translational modifications than those already in the FindMod/FindPept Database, you can specify them here:

modification name abbreviationatom compositionpositions
H: , O: , C: , N: , S: , P: 
86 M
H: , O: , C: , N: , S: , P: 
H: , O: , C: , N: , S: , P: 

All peptide masses are
with cysteines treated with:
with methionines oxidized
with tryptophans oxidized
with acidic and C-terminal residues esterified
with possible N-Acetylation or N-Formylation
[M+H]+ or [M] or [M-H]-.
average or monoisotopic.

Mass tolerance: ±

Display peptides sorted by peptide masses or in chronological order in the protein.

If you select a protease below, the peptide masses will be checked for specific cleavage as well as autolytic cleavage of the enzyme.
Select an enzyme (Optional) :
Exclude masses that match: specific cleavage by the enzyme
  autolytic cleavage of the enzyme
  specific cleavage of human keratins

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

To run the search:
To clear all fields: