PeptIdent

PeptIdent is a tool that allows the identification of proteins using pI, Mw and peptide mass fingerprinting data.
Experimentally measured, user-specified peptide masses are compared with the theoretical peptides calculated for all proteins in the Swiss-Prot/TrEMBL databases. A species (or group of species) can also be specified for the search.

PeptIdent makes extensive use of the annotations in Swiss-Prot:

When calculating the theoretical peptides from Swiss-Prot, PeptIdent removes signal sequences and/or propeptides (as documented in the Swiss-Prot feature table (FT lines)) before computing pI, Mw and peptide masses for each of the resulting chains.
The program takes into account post-translational modifications and alternative splicing events as documented in Swiss-Prot.

Results are displayed on-line in your browser window or can be sent by email, in form of a html table. The email option is recommended, especially for queries with many peptide masses, large pI/Mw windows or all species.

The result file contains direct links to FindMod, GlycoMod and FindPept, to further characterize matching proteins by predicting potential protein post-translational modifications and finding potential single amino acid substitutions or non-specific cleavage, and to PeptideMass. It further contains, for each matching protein, a link to the BioGraph tool which allows to graphically represent the results of the PeptIdent query.

Note: PeptIdent has been designed for Netscape 3.0, Internet Explorer 3.0 or better. Should you be using an older version, we highly recommend you upgrade your browser in order to enjoy the full functionality of the program.

Documentation is available.

Peptide Mass Fingerprinting

Name of the unknown protein:
Database:
Note: Peptides with masses >6000 Da have not been indexed.

pI: within pI range:
Mw: (in Dalton, not kDa!) within Mw range (in percent):

Species to be searched:

Enter a list of peptide masses (separated by spaces or newlines) that correspond to the unknown protein:

Or upload a file in one of the supported formats from your computer The peptide masses will be extracted automatically from this file:

All peptide masses are: [M+H]⁺ or [M] or [M-H]^-, and
monoisotopic or average.
The peptide masses are: with cysteines treated with:; with acrylamide adducts on cysteines; with methionines oxidized.

Mass tolerance: ±

Enzyme:

Allow for missed cleavage sites (MC).

Report only proteins with at least peptide hits.

Display a maximum of matching proteins.

Print information about sequence portion covered by the matching peptides.

Send the result by e-mail: With this option, you will receive the result (in form of an html table) by e-mail. This is recommended and helps avoid the otherwise frequent 'Document contains no data' timeout errors, especially for queries with many peptide masses, large pI/Mw windows or all species.
Your e-mail address:

To run the search:
To clear all fields:

Last modified 14/Jun/2002 by ELG

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