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PeptideMass

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PeptideMass

PeptideMass [Documentation / References] cleaves a protein sequence from the UniProt Knowledgebase (Swiss-Prot and TrEMBL) or a user-entered protein sequence with a chosen enzyme, and computes the masses of the generated peptides. The tool also returns theoretical isoelectric point and mass values for the protein of interest. If desired, PeptideMass can return the mass of peptides known to carry post-translational modifications, and can highlight peptides whose masses may be affected by database conflicts, polymorphisms or splice variants.


Submit a protein sequence

Please enter one UniProtKB AC/ID (e.g. P04406 or ALBU_HUMAN). Alternatively, enter one protein sequence in single letter code (e.g. ABCDEFGHIKLMNOPQRSTUVWXY);
you may specify post-translational modifications (PTMs), if you do, PLEASE read this documentation first.

Examples


OR

Cysteines and methionines modifications

The peptide masses are
with cysteines treated with:
with acrylamide adducts
with methionines oxidized
[M+H]+ or [M] or [M-H]- or [M+2H]2+ or [M+3H]3+

Mass calculation

average or monoisotopic.

Enzyme

Select an enzyme:
Allow for missed cleavages.

Output

Display the peptides with a mass bigger than and smaller than Dalton
sorted by peptide masses or in chronological order in the protein.

For UniProtKB (Swiss-Prot/TrEMBL) entries only:

For each peptide displayed, show:
all known post-translational modifications,
all database conflicts,
all variants (polymorphisms ),
all mRNA variants (due to alternative splicing, initiation or promoter usage).


OR