| Peptide Information Explanation
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| Extracted from ProteinScape 3.0 User Manual Revision 1, page 154-155, Mascot Help – Matrix Science web
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| Cell cycle phase/MS
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Coding (G1, S, G2) refers to a specific protein sample prepared by extraction from the corresponding phase of the cell cycle. The abbreviation after the slash mark indicates the ionization technique used for protein identification by mass spectrometry of peptides. MALDI and ESI represent measurement on MALDI-TOF/TOF and ESI-QqTOF instrument, respectively.
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| Sequence
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The sequence of the identified peptide written using the 1-letter code is placed here. The residues that bracket the peptide sequence in the protein are also shown, delimited by dots. If the peptide forms the protein terminus, then a dash is shown instead.
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| m/z measured
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The measured (experimental) mass-to-charge ratio of the identified peptide is provided here.
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| MH+ measured
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This is the single protonated monoisotopic mass of the identified peptide. It is calculated from the m/z value.
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| Delta m/z (Da)/(ppm)
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The difference in mass-to-charge ratio shown here is represented by a difference (error) between the experimental and theoretically calculated masses.
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| z
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z means the charge state of the identified peptide.
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| Retention time (min)
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This value shows the retention time (in minutes) of the peptide during chromatographic separation.
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| Intensity
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This value refers to the precursor ion intensity, which means the intensity of peptide precursor selected for fragmentation in the collision cell during mass spectrometric analysis.
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| MCV
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This value represents the number of partials (missed cleavages). A missed cleavage is generated at a position in the given sequence where the proteolytic enzyme is theoretically expected to cleave because of its specificity, but the cleavage does not occur during proteolytic digestion.
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| Position range
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This is the localization of the identified peptide in the respective protein sequence. The protein sequence is numbered starting from the N-terminal residue.
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| Peptide score (Mascot)
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The Ion peptide score in the format of Mascot algorithm (Matrix Science). In Mascot, the ions score for an MS/MS match is based on the calculated probability, P, that the observed match between the experimental data and the database sequence is a random event. The reported score is -10Log(P). Deep description of an ion score is explained at web of Matrix Science ( http://www.matrixscience.com/help/interpretation_help.html ).
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| Modifications
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This refers to chemical modifications present in the identified peptide. The number represents the position of the modified amino acid residue in the peptide sequence starting with 1 for the N-terminal residue of the identified peptide.
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