New Modification
        
        
        Type
        The type of modification has to be specified according to OMSSA standards:
        
            - modaa -- modification at particular amino acids
- modn -- at the N terminus of a protein
- modnaa -- at the N terminus of a protein at particular amino acids
- modc -- at the C terminus of a protein
- modcaa -- at the C terminus of a protein at particular amino acids
- modnp -- at the N terminus of a peptide
- modnpaa -- at the N terminus of a peptide at particular amino acids
- modcp -- at the C terminus of a peptide
- modcpaa -- at the C terminus of a peptide at particular amino acids
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        Name
        The name of the modification should be unique and not contain '_'.
        
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        Mass
        Please type here the monoisotopic mass of the modification. Average mass is currently not 
        supported. If needed, please contact the developers.
        
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        Residues
        For some types of modification, it is necessary to specify the amino acids concerned by the 
        modification. Please type the single letter coded amino-acids separated by a comma (for example: "S, T, Y").
        
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        Neutral Losses
        Some modifications can result in so-called neutral losses. This can result in fragment ions 
        with a mass lower than the normal mass of the fragment ion. The most common neutral losses 
        are water and ammonia. There are also neutral losses related to phosphorylation, e.g., H3PO4 (97.97689499).
        
        Neutral losses can be either fixed or variable. A fixed neutral loss means that the loss 
        always occurs. Fixed neutral losses should be used with care as they affect how the search engines 
        treat the modification itself.
        
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        Reporter Ions
        Reporter ions are ions that can be used as indicators that the peptide is modified by a 
        given modification. The most common reporter ions are iTRAQ and TMT marker ions. But reporter 
        ions can also be found for other modifications, e.g., 126 (and 143) for lysine acetylation, 
        and 216.043 for phosphorylation of tyrosine.
        
        Please provide the mass of the reporter ion as m/z, i.e., the exact m/z value of the peak you want to annotate.
        
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        Unimod Mapping
        If the search results are to be later opened in PeptideShaker and then submitted to 
        PRIDE it is recommended to map the user defined modifications to the standard Unimod 
        modifications (http://www.unimod.org). This ensures that the given modification is understood in 
        the same way by all users. For example, Oxidation is Unimod accession 35.
        
        Find the wanted modification and insert the Unimod accession number and Unimod name. The Unimod modification name is listed as PSI-MS Name 
        (or as Interim Name if no PSI-MS Name is given). For example, for oxidation: accession:35 and PSI-MS Name:Oxidation.
        
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