The following table describes the types of information in the lower section of the Modification Results table on the Modification Summary page.

Modification Results table, lower section parameters

Parameter

Description

Field Chooser

Displays the Field Chooser dialog box so that you can select the columns to display in the lower section of the Modification Results pane.

(Check box)

Select or clear the checkbox in the table header row to select/deselect all rows in the lower section.

You can also select the checkbox in individual rows for export.

Protein

Displays the protein sequence.

Residue #

Displays the amino acid residue (site) number of the modification within the protein sequence.

Modification

Displays the type and site of modification.

Category

Displays the type of modification by category.

  • Unknown Modification: Modifications identified using the Mass Search for Unspecified Modifications functionality when the application cannot identify the exact location of the modification. Unknown modifications are indicated by a tilde (~).
  • Modification: Common modifications.
  • Artifact: Modifications resulting from sampling errors.
  • Sequence Variant: Modifications from sequence variants.
  • N-Glycan or O-Glycan: Modifications from N-linked or O-linked glycans.

Comment

Displays any comments about the modification to support the identification, the % Abundance, or both.

Examples of comments include None, Possible artifact, or Poor recovery.

Normalized Time Shift (NTS)

Displays the experimental shift of the retention time after modification as a percentage of the abundance-weighted average retention time of all identified components.

A negative NTS values indicates that the modified peptide elutes earlier than the unmodified peptide.

A positive NTS value indicates that the modified peptide elutes later than the unmodified peptide.

Predicted Time Shift

Displays the predicted retention time shift for a modified component compared to the unmodified component.

This parameters is based on empirically-determined Normalized Time Shift values of common modifications.

Peptides

Displays the peptide sequence range and sequence mass for the component within the protein.

Peptide Sequence

Displays the peptide sequence for the component.

Confidence

Displays the confidence score for the modification assignment.

Recovery

Displays the general abundance of the component.

This value is the total peak area (including modified and unmodified forms of the component) as a percentage of the self-weighted average of all components. The recovery value can be over 100% because of the way the application calculates the reference peak intensity.

  • Good: Recovery > 10%
  • Fair: 1% < Recovery < 10%
  • Poor: Recovery < 1%

% Abundance raw_data_file_name

Displays the % Abundance value for a modification in a particular raw data file.

Custom % Abundance raw_data_file_name

Displays the custom % Abundance value for a modification in a particular raw data file.

Visible only when you change the list of components used for the % Abundance calculation.