Output

This document describes the output produced by the pipeline

Pipeline overview

The final output of the pipeline should include the following files:

• mzTab - the community standard format for sharing mass spectrometry search results
• csv - aggregate csv report, containing all information about peptide identification and quantification results

mzTab

mzTab is a light-weight format to report mass spectrometry search results. It provides all important information about idenfied peptide hits and is compatible with the PRIDE Archive - proteomics data repository:

Griss, J. et al. The mzTab Data Exchange Format: Communicating Mass-spectrometry-based Proteomics and Metabolomics Experimental Results to a Wider Audience. Mol Cell Proteomics 13, 2765–2775 (2014).

csv

The csv output file is a table containing all information extracted from a database search throughout the pipeline. See the OpenMS or PSI documentation for more information about annotated scores and format (http://ftp.mi.fu-berlin.de/pub/OpenMS/release1.9-documentation/html/TOPP_TextExporter.html).

Each row index is represented by a label describing its content:

#MAP    id      filename        label   size

#MAP contains information about the different mzML files that were provided initially

#RUN    run_id  score_type      score_direction date_time       search_engine_version   parameters

#RUN contains information about the search that was performed on each run

#PROTEIN        score   rank    accession       protein_description     coverage        sequence

#PROTEIN contains infomration about the protein ids corresponding to the peptides that were detected (No protein inference was performed)

#UNASSIGNEDPEPTIDE      rt      mz      score   rank    sequence        charge  aa_before       aa_after        score_type      search_identifier       accessions      FFId_category   feature_id      file_origin     map_index       spectrum_reference      COMET:IonFrac   COMET:deltCn    COMET:deltLCn   COMET:lnExpect  COMET:lnNumSP   COMET:lnRankSP  MS:1001491      MS:1001492      MS:1001493      MS:1002252      MS:1002253      MS:1002254      MS:1002255      MS:1002256      MS:1002257      MS:1002258      MS:1002259      num_matched_peptides    protein_references      target_decoy

#UNASSIGNEDPEPTIDE contains information about PSMs that were identified but couldn’t be quantified to a precursor feature on MS Level 1

#CONSENSUS      rt_cf   mz_cf   intensity_cf    charge_cf       width_cf        quality_cf      rt_0    mz_0    intensity_0     charge_0        width_0 rt_1    mz_1    intensity_1     charge_1        width_1 rt_2    mz_2    intensity_2     charge_2        width_2 rt_3    mz_3    intensity_3     charge_3        width_3

#CONSENSUS contains information about precursor features that were identified in multiple runs (eg. run 1-3 in this case)

#PEPTIDE        rt      mz      score   rank    sequence        charge  aa_before       aa_after        score_type      search_identifier       accessions      FFId_category   fea

#PEPTIDE contains information about peptide hits that were identified and correspond to the consensus features described one row above.

Predictions

The prediction output is a comma separated table (csv) for each allele, listing each peptide sequence and its corresponding predicted affinity scores:

peptide   allele   prediction   prediction_low   prediction_high   prediction_percentile