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FindPept

FindPept

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].

Run FindPept


1. Enter a sequence (mandatory):
Please enter one UniProtKB AC/ID (e.g. P20366 or TKN1_HUMAN). Alternatively, enter one protein sequence in single letter code.
You may specify post-translational modifications, as specified in this document
Examples


2. Enter a list of peptide masses and intensities (optional):
Enter a list of peptide masses and intensities (optional) that correspond to the specified protein. Enter one mass, space and its intensity per line:
Examples

Or upload a file from your computer, from which the peptide masses will be extracted (supported formats):


3. Other PTMs to take into account (optional):
If you wish to take into account other PTMs than those already predictable by FindMod and FindPept tools, you can specify them here:

modification name amino acids
this modification
can be observed on 		atom composition positions
0 example OXYD H: -2, O: 1, C:, N:, S: 86M
1 H: , O: , C: , N: , S:
2 H: , O: , C: , N: , S:


4. Choose cysteine treatment (optional):
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


5.Choose other parameters (optional):
Mass tolerance: ±
Select an enzyme:
If you select a protease below, the peptide masses will be checked for specific cleavage as well as autolytic cleavage of the enzyme.
Exclude masses that match:
specific cleavage by the enzyme
autolytic cleavage of the enzyme
specific cleavage of human keratins
Display peptides sorted by peptide masses or in chronological order in the protein.


6. Send the results by e-mail (optional):
Your e-mail address:
Name of the unknown protein:


7. Submit or reset: