Beispiel #1
0
 void OpenSwathHelper::selectSwathTransitions(const OpenMS::TargetedExperiment& targeted_exp,
                                              OpenMS::TargetedExperiment& transition_exp_used, double min_upper_edge_dist,
                                              double lower, double upper)
 {
   transition_exp_used.setPeptides(targeted_exp.getPeptides());
   transition_exp_used.setProteins(targeted_exp.getProteins());
   for (Size i = 0; i < targeted_exp.getTransitions().size(); i++)
   {
     ReactionMonitoringTransition tr = targeted_exp.getTransitions()[i];
     if (lower < tr.getPrecursorMZ() && tr.getPrecursorMZ() < upper &&
         std::fabs(upper - tr.getPrecursorMZ()) >= min_upper_edge_dist)
     {
       transition_exp_used.addTransition(tr);
     }
   }
 }
Beispiel #2
0
  void MRMDecoy::generateDecoys(OpenMS::TargetedExperiment& exp, OpenMS::TargetedExperiment& dec,
                                String method, String decoy_tag, double identity_threshold, int max_attempts,
                                double mz_threshold, double mz_shift, bool exclude_similar,
                                double similarity_threshold, bool remove_CNterminal_mods, double precursor_mass_shift,
                                std::vector<String> fragment_types, std::vector<size_t> fragment_charges,
                                bool enable_specific_losses, bool enable_unspecific_losses, bool remove_unannotated,
                                int round_decPow)
  {
    MRMIonSeries mrmis;
    MRMDecoy::PeptideVectorType peptides, decoy_peptides;
    MRMDecoy::ProteinVectorType proteins, decoy_proteins;
    MRMDecoy::TransitionVectorType decoy_transitions;
    for (Size i = 0; i < exp.getProteins().size(); i++)
    {
      OpenMS::TargetedExperiment::Protein protein = exp.getProteins()[i];
      protein.id = decoy_tag + protein.id;
      proteins.push_back(protein);
    }

    std::vector<String> exclusion_peptides;
    // Go through all peptides and apply the decoy method to the sequence
    // (pseudo-reverse, reverse or shuffle). Then set the peptides and proteins of the decoy
    // experiment.
    for (Size pep_idx = 0; pep_idx < exp.getPeptides().size(); ++pep_idx)
    {
      OpenMS::TargetedExperiment::Peptide peptide = exp.getPeptides()[pep_idx];
      // continue if the peptide has C/N terminal modifications and we should exclude them
      if (remove_CNterminal_mods && MRMDecoy::has_CNterminal_mods(peptide)) {continue; }
      peptide.id = decoy_tag + peptide.id;
      OpenMS::String original_sequence = peptide.sequence;
      if (!peptide.getPeptideGroupLabel().empty())
      {
        peptide.setPeptideGroupLabel(decoy_tag + peptide.getPeptideGroupLabel());
      }

      if (method == "pseudo-reverse")
      {
        peptide = MRMDecoy::pseudoreversePeptide(peptide);
      }
      else if (method == "reverse")
      {
        peptide = MRMDecoy::reversePeptide(peptide);
      }
      else if (method == "shuffle")
      {
        peptide = MRMDecoy::shufflePeptide(peptide, identity_threshold, -1, max_attempts);
      }
      for (Size prot_idx = 0; prot_idx < peptide.protein_refs.size(); ++prot_idx)
      {
        peptide.protein_refs[prot_idx] = decoy_tag + peptide.protein_refs[prot_idx];
      }

      if (MRMDecoy::AASequenceIdentity(original_sequence, peptide.sequence) > identity_threshold)
      {
        if (!exclude_similar)
        {
          std::cout << "Target sequence: " << original_sequence << " Decoy sequence: " << peptide.sequence  << " Sequence identity: " << MRMDecoy::AASequenceIdentity(original_sequence, peptide.sequence) << " Identity threshold: " << identity_threshold << std::endl;
          throw Exception::IllegalArgument(__FILE__, __LINE__, OPENMS_PRETTY_FUNCTION, "AA Sequences are too similar. Either decrease identity_threshold and increase max_attempts for the shuffle method or set flag exclude_similar.");
        }
        else
        {
          exclusion_peptides.push_back(peptide.id);
        }
      }

      peptides.push_back(peptide);
    }
    dec.setPeptides(peptides); // temporary set peptides, overwrite later again!

    // hash of the peptide reference containing all transitions
    MRMDecoy::PeptideTransitionMapType peptide_trans_map;
    for (Size i = 0; i < exp.getTransitions().size(); i++)
    {
      peptide_trans_map[exp.getTransitions()[i].getPeptideRef()].push_back(&exp.getTransitions()[i]);
    }

    Size progress = 0;
    startProgress(0, exp.getTransitions().size(), "Creating decoys");
    for (MRMDecoy::PeptideTransitionMapType::iterator pep_it = peptide_trans_map.begin();
         pep_it != peptide_trans_map.end(); ++pep_it)
    {
      String peptide_ref = pep_it->first;
      String decoy_peptide_ref = decoy_tag + pep_it->first; // see above, the decoy peptide id is computed deterministically from the target id
      const TargetedExperiment::Peptide target_peptide = exp.getPeptideByRef(peptide_ref);
      // continue if the peptide has C/N terminal modifications and we should exclude them
      if (remove_CNterminal_mods && MRMDecoy::has_CNterminal_mods(target_peptide)) {continue;}

      const TargetedExperiment::Peptide decoy_peptide = dec.getPeptideByRef(decoy_peptide_ref);
      OpenMS::AASequence target_peptide_sequence = TargetedExperimentHelper::getAASequence(target_peptide);
      OpenMS::AASequence decoy_peptide_sequence = TargetedExperimentHelper::getAASequence(decoy_peptide);

      int decoy_charge = 1;
      int target_charge = 1;
      if (decoy_peptide.hasCharge()) {decoy_charge = decoy_peptide.getChargeState();}
      if (target_peptide.hasCharge()) {target_charge = target_peptide.getChargeState();}

      MRMIonSeries::IonSeries decoy_ionseries = mrmis.getIonSeries(decoy_peptide_sequence, decoy_charge, fragment_types, fragment_charges, enable_specific_losses, enable_unspecific_losses, round_decPow);
      MRMIonSeries::IonSeries target_ionseries = mrmis.getIonSeries(target_peptide_sequence, target_charge, fragment_types, fragment_charges, enable_specific_losses, enable_unspecific_losses, round_decPow);

      for (Size i = 0; i < pep_it->second.size(); i++)
      {
        setProgress(++progress);
        const ReactionMonitoringTransition tr = *(pep_it->second[i]);

        if (!tr.isDetectingTransition() || tr.getDecoyTransitionType() == ReactionMonitoringTransition::DECOY)
        {
          continue;
        }

        ReactionMonitoringTransition decoy_tr = tr; // copy the target transition

        decoy_tr.setNativeID(decoy_tag + tr.getNativeID());
        decoy_tr.setDecoyTransitionType(ReactionMonitoringTransition::DECOY);
        decoy_tr.setPrecursorMZ(tr.getPrecursorMZ() + precursor_mass_shift); // fix for TOPPView: Duplicate precursor MZ is not displayed.

        // determine the current annotation for the target ion and then select
        // the appropriate decoy ion for this target transition
        std::pair<String, double> targetion = mrmis.annotateIon(target_ionseries, tr.getProductMZ(), mz_threshold);
        std::pair<String, double> decoyion = mrmis.getIon(decoy_ionseries, targetion.first);

        if (method == "shift")
        {
          decoy_tr.setProductMZ(decoyion.second + mz_shift);
        }
        else
        {
          decoy_tr.setProductMZ(decoyion.second);
        }
        decoy_tr.setPeptideRef(decoy_tag + tr.getPeptideRef());

        if (decoyion.second > 0)
        {
          if (similarity_threshold >= 0)
          {
            if (std::fabs(tr.getProductMZ() - decoy_tr.getProductMZ()) < similarity_threshold)
            {
              if (!exclude_similar)
              {
                throw Exception::IllegalArgument(__FILE__, __LINE__, OPENMS_PRETTY_FUNCTION, "Fragment ions are too similar. Either decrease similarity_threshold or set flag exclude_similar.");
              }
              else
              {
                exclusion_peptides.push_back(decoy_tr.getPeptideRef());
              } 
           }
          }
          decoy_transitions.push_back(decoy_tr);
        }
        else
        {
          if (remove_unannotated)
          {
            exclusion_peptides.push_back(decoy_tr.getPeptideRef());
          }
          else
          {
            throw Exception::IllegalArgument(__FILE__, __LINE__, OPENMS_PRETTY_FUNCTION, "Decoy fragment ion for target fragment ion " + String(targetion.first) + " of peptide " + target_peptide_sequence.toString() + " with precursor charge " + String(target_peptide.getChargeState()) + " could not be mapped. Please check whether it is a valid ion and enable losses or removal of terminal modifications if necessary. Skipping of unannotated target assays is available as last resort.");
          }
        }
      } // end loop over transitions
    } // end loop over peptides
    endProgress();

    MRMDecoy::TransitionVectorType filtered_decoy_transitions;
    for (MRMDecoy::TransitionVectorType::iterator tr_it = decoy_transitions.begin(); tr_it != decoy_transitions.end(); ++tr_it)
    {
      if (std::find(exclusion_peptides.begin(), exclusion_peptides.end(), tr_it->getPeptideRef()) == exclusion_peptides.end())
      {
        filtered_decoy_transitions.push_back(*tr_it);
      }
    }
    dec.setTransitions(filtered_decoy_transitions);

    std::vector<String> protein_ids;
    for (Size i = 0; i < peptides.size(); ++i)
    {
      TargetedExperiment::Peptide peptide = peptides[i];

      // Check if peptide has any transitions left
      if (std::find(exclusion_peptides.begin(), exclusion_peptides.end(), peptide.id) == exclusion_peptides.end())
      {
        decoy_peptides.push_back(peptide);
        for (Size j = 0; j < peptide.protein_refs.size(); ++j)
        {
          protein_ids.push_back(peptide.protein_refs[j]);
        }
      }
      else
      {
        LOG_DEBUG << "[peptide] Skipping " << peptide.id << std::endl;
      }
    }

    for (Size i = 0; i < proteins.size(); ++i)
    {
      OpenMS::TargetedExperiment::Protein protein = proteins[i];

      // Check if protein has any peptides left
      if (find(protein_ids.begin(), protein_ids.end(), protein.id) != protein_ids.end())
      {
        decoy_proteins.push_back(protein);
      }
      else
      {
        LOG_DEBUG << "[protein] Skipping " << protein.id << std::endl;
      }
    }

    dec.setPeptides(decoy_peptides);
    dec.setProteins(decoy_proteins);

  }