For Top Down Analysis experiments involving MS/MS data, the ProSightBP Fragment Map pane on the Process and Review page displays the proteoform-specific fragment map generated by the ProSight Lite application after processing the MS/MS spectra. A fragment map shows the location of the PTMs and matching fragment ions within a protein (proteoform) sequence.
Procedure
- Open the results of your experiment from the Queue page or from the Load Results page.
- The Process and Review page opens by default and displays the results of your Top Down Analysis experiment, including the ProSightBP Fragment Map (if applicable).
- On the Process and Review page, select the Intact Fragmentation Results tab at the bottom left (if necessary).
- Select the ProSightBP Fragment Map subtab (next to the ProSightBP Output subtab) at the bottom right (if necessary).
- Select the row of a peak in the Intact Fragmentation Results table.
- The ProSightBP Fragment Map pane displays the fragment maps containing the identified fragment ion results for all of the proteoforms processed under the selected peak.
- The name of each proteoform appears above each map, followed by the name of the loaded raw data file (for a batch experiment or there an experiment with only one loaded raw data file) or "Combined Results" (for a multiconsensus experiment with multiple loaded files), and finally the Residue Cleavages (%) value.
Figure ProSightBP Fragment Map pane - If there is only one proteoform generated for the experiment, only one map appears showing the identified fragment ions for that proteoform.
- If there are multiple proteoforms generated for the experiment, multiple maps appear. The first map contains the results from the unmodified sequence (if you select to include it as a searched proteoform), followed by one map for each of the generated proteoforms, stacked one on top of the other.
- If you load only one raw data file for the experiment or you are running a batch experiment, the results for each map are from one file.
- If you load multiple files for a multiconsensus experiment, the results for each map are from the combined results. To generate the combined results, the application sends the MS/MS deconvolution mass results from each individual raw data file to the ProSight Lite application for searching. After receiving the individual search results, the application then combines them for display.
- Interpret the ProSight fragment map results for your Top Down Analysis experiment according to the following information:
- •The map lists the amino acid letters in the protein sequences from left to right and from top to bottom.
- •The gray "N" at the top left corner of the map represents the N-terminal of the proteoform.
- •The gray "C" at the bottom of the map represents the C-terminal.
- •All cysteine (C) residues appear in yellow.
- •All modified amino acids appear with green backgrounds.
- When you hover your cursor over an individual amino acid letter, a tool-tip box appears showing the corresponding residue number.
- The map also contains different vertical bars, depending on the identified ion type:
- •A red bar with a serif at the top pointing left represents the termination of a c ion.
- •A red bar with a serif at the bottom pointing right represents the start of a z ion.
- •A blue bar with a serif at the top pointing left represents the termination of a b ion.
- •A blue bar with a serif at the bottom pointing right represents the start of a y ion.
- •A green bar with a serif at the top pointing left represents the termination of an a ion.
- •A green bar with serif at the bottom pointing right represents the start of an x ion.
- These bars can overlap if combinations of identified ions exist.
- When you hover your cursor over a colored bar, a tool-tip box appears showing the identified fragment ion type, mass (measured in Da), and number of identifications.
- Double-click a colored bar or a set of overlapping colored bars on a fragment map.
- The Matching Fragment Detail dialog box appears, displaying the masses and mass differences for the selected bars.
Figure Matching Fragment Detail dialog box - Each row in the table represents one identified fragment ion for the selected location in the sequence.
- See Matching Fragment Detail table parameters.
- You can save an image (as a .png file) of the ProSightBP Fragment Map by right-clicking in the pane and selecting "Save as (.png)" from the shortcut menu.
- See ProSightBP Fragment Map pane commands.