//method was originally written recursively, but large peptides result in stackoverflow exceptions
public void MassMatch(string B, string Y, PSM psm, int BIndex, int YIndex, out string error_message) //this is the workhorse of SpliceFragments
{
error_message = "";
test = psm.getScan().ToString();
double ExperimentalMass = psm.getExpMass();
string BFrag = IonCrop(B, ExperimentalMass, BIndex, IonType.b, false, out string e4); //returns a B ion sequence that has a mass smaller than the experimental mass by cleaving C term AA
//BIndex = B.Length - BFrag.Length; //added 11/8/16 Useful first pass to record how many AA have been cleaved from C term
string YFrag = IonCrop(Y, ExperimentalMass, YIndex, IonType.y, false, out string e3); //returns a Y ion sequence that has a mass smaller than the experimental mass by cleaving N term AA
//YIndex = Y.Length - YFrag.Length; //added 11/8/16 Useful first pass to record how many AA have been cleaved from N term
double TheoreticalMass = MassCalculator.MonoIsoptopicMass(BFrag, out string e) + MassCalculator.MonoIsoptopicMass(YFrag, out string e2) - Constants.WATER_MONOISOTOPIC_MASS + fixedModMass; //water added once in b and once in y
error_message += e3 + e4 + e + e2;
//add PTM masses
foreach (PTM ptm in psm.getNInfo().getPTMs())
{
if (ptm.index < BFrag.Length)
{
TheoreticalMass += ptm.mass;
}
}
foreach (PTM ptm in psm.getCInfo().getPTMs())
{
if (Y.Length - ptm.index < YFrag.Length)
{
TheoreticalMass += ptm.mass;
}
}
if (YFrag.Length < ionsUsedMassVer) //If the number of AA from the C-term peptide is less than desired amount, end recursion.
{
//we're done
}
else if (BFrag.Length < ionsUsedMassVer) //If the number of AA from the N-term peptide is less than desired amount, start over loop and remove a single aa from the C-term
{
// MassMatch(B, Y, psm, 0, YIndex+1);
}
//if match
//bool elif = true; //"else if" where not a match==true
else if (FalsePositives.generateDecoys)
{
//else if (((TheoreticalMass - Constants.PEPTIDE_N_TERMINAL_MONOISOTOPIC_MASS * 7) > (ExperimentalMass - 1 * Constants.PEPTIDE_N_TERMINAL_MONOISOTOPIC_MASS) && (TheoreticalMass - Constants.PEPTIDE_N_TERMINAL_MONOISOTOPIC_MASS * 7) < (ExperimentalMass + 1 * Constants.PEPTIDE_N_TERMINAL_MONOISOTOPIC_MASS)) | ((TheoreticalMass + Constants.PEPTIDE_N_TERMINAL_MONOISOTOPIC_MASS * 7) > (ExperimentalMass - 1 * Constants.PEPTIDE_N_TERMINAL_MONOISOTOPIC_MASS) && (TheoreticalMass + Constants.PEPTIDE_N_TERMINAL_MONOISOTOPIC_MASS * 7) < (ExperimentalMass + 1 * Constants.PEPTIDE_N_TERMINAL_MONOISOTOPIC_MASS)))//if match //if ((TheoreticalMass) > (ExperimentalMass+ i -PrecursorMassToleranceDa) && (TheoreticalMass) < (ExperimentalMass+i +PrecursorMassToleranceDa)) //if match
if (((TheoreticalMass) > (ExperimentalMass - 9.5) && (TheoreticalMass) < (ExperimentalMass - 4.5)) | ((TheoreticalMass) > (ExperimentalMass + 5.5) && (TheoreticalMass) < (ExperimentalMass + 7.5)))//if match //if ((TheoreticalMass) > (ExperimentalMass+ i -PrecursorMassToleranceDa) && (TheoreticalMass) < (ExperimentalMass+i +PrecursorMassToleranceDa)) //if match //else if(Math.Abs(ExperimentalMass - TheoreticalMass)<40 && (ExperimentalMass - TheoreticalMass)-Math.Floor(ExperimentalMass-TheoreticalMass)>0.3 && (ExperimentalMass - TheoreticalMass) - Math.Floor(ExperimentalMass - TheoreticalMass) < 0.8)
{
// elif = false;
bool previouslyFound = false;
foreach (FusionCandidate oldCandidate in psm.getFusionCandidates())
{
if ((BFrag + YFrag).Equals(oldCandidate.seq)) //see if that sequence was already recorded
{
previouslyFound = true;
}
}
if (!previouslyFound) //if fusion sequence was not previously assigned to this psm
{
FusionCandidate candidate = new FusionCandidate(BFrag + YFrag);
psm.addFusionCandidate(candidate);
// MassMatch(B, Y, psm, BIndex + 1, YIndex);
}
}
}
else
{
if ((TheoreticalMass) > (ExperimentalMass * (1 - FalsePositives.precursorMassTolerancePpm / 1000000)) && (TheoreticalMass) < (ExperimentalMass * (1 + FalsePositives.precursorMassTolerancePpm / 1000000))) //if match //if ((TheoreticalMass) > (ExperimentalMass+ i -PrecursorMassToleranceDa) && (TheoreticalMass) < (ExperimentalMass+i +PrecursorMassToleranceDa)) //if match
{
// elif = false;
bool previouslyFound = false;
foreach (FusionCandidate oldCandidate in psm.getFusionCandidates())
{
if ((BFrag + YFrag).Equals(oldCandidate.seq)) //see if that sequence was already recorded
{
previouslyFound = true;
}
}
if (!previouslyFound) //if fusion sequence was not previously assigned to this psm
{
FusionCandidate candidate = new FusionCandidate(BFrag + YFrag);
psm.addFusionCandidate(candidate);
// MassMatch(B, Y, psm, BIndex + 1, YIndex);
}
}
}
// if(elif) //not a match
{
/* if (TheoreticalMass < ExperimentalMass && BIndex == 0) //first pass, theo less than exp and can't take away more ions
* {
* //we're done
* }
* else
* {
* if (TheoreticalMass < ExperimentalMass) //if b out of ions, but y not, crop off a y and start again
* {
* BIndex = 0;
* YIndex++;
* MassMatch(B,Y, psm, BIndex, YIndex);
* }
* else
* { //crop off a b ion
* MassMatch(B, Y, psm, BIndex + 1, YIndex);
* }
* }*/
}
}
//returns true if a full fusion sequence could not be made or was found in the database, making it translated instead of a novel fusion.
public bool PossibleCandidate(PSM psm)
{
foundSequences = new Dictionary <string, List <TheoreticalProtein> >(); //used for finding longer fragments than those previously identified. Also populates ParentInfo
notFoundSequences = new HashSet <string>(); //don't bother looking for these fragments, since we know they don't exist. Good for multiple homologous putative fusion peptide sequences
//conduct an initial search of each candidate's full sequence to identify any that are translated
for (int i = 0; i < psm.getFusionCandidates().Count(); i++) //foreach fusion peptide sequence that could map to this scan
{
string novelSeq = psm.getFusionCandidates()[i].seq;
if (foundParent(novelSeq, ParentInfo.terminal.C, psm.getFusionCandidates()[i], false)) //check really quick to see if the whole thing exists as is. If so, assign it as translated. Terminal C was arbitrarily chosen
{
foreach (ParentInfo info in psm.getFusionCandidates()[i].parentInfo)
{
foreach (TheoreticalProtein protein in info.theoreticalProteins)
{
if (protein.seq.Contains(novelSeq)) //if translated
{
psm.getFusionCandidates()[i].translatedParents.Add(new TranslatedParent(protein.id, protein.seq, protein.seq.IndexOf(psm.getFusionCandidates()[i].seq), psm.getFusionCandidates()[i].seq.Length));
}
}
}
psm.getFusionCandidates()[i].fusionType = FusionCandidate.FusionType.TL;
psm.fusionType = psm.getFusionCandidates()[i].fusionType;
for (int j = 0; j < psm.getFusionCandidates().Count(); j++)
{
if (j != i)
{
psm.getFusionCandidates().Remove(psm.getFusionCandidates()[j]);
j--;
i--;
}
}
return(true);
}
}
for (int i = 0; i < psm.getFusionCandidates().Count(); i++) //foreach fusion peptide sequence that could map to this scan
{
//sw.StartFindParents
if (!isViable(psm.getFusionCandidates()[i])) //remove this fusion peptide sequence if the parent fragments cannot be found with the given database
{
psm.getFusionCandidates().Remove(psm.getFusionCandidates()[i]);
i--;
}
else
{
DetermineFusionCandidateType(psm.getFusionCandidates()[i]); //cis, trans?
if (psm.fusionType > psm.getFusionCandidates()[i].fusionType) //if more likely than previous types, change the psm type (golf scoring)
{
psm.fusionType = psm.getFusionCandidates()[i].fusionType;
}
if (psm.fusionType.Equals(FusionCandidate.FusionType.TL))//if there's a possible sequence that's present in the database, it is likely correct and is it is not worth it to identify parents of other sequences.
{
//remove all other candidates
for (int j = 0; j < psm.getFusionCandidates().Count(); j++)
{
if (j != i)
{
psm.getFusionCandidates().Remove(psm.getFusionCandidates()[j]);
j--;
i--;
}
}
return(true);
}
}
}
if (psm.getFusionCandidates().Count() == 0) //if no candidates are left, we couldn't make the sequence with the database and we'll discard it.
{
return(false);
}
return(true);
}
public bool IsTooMessy(PSM psm, out string error_message) //return true if too messy for confident identification
{
error_message = "";
List <string> baseSequences = new List <string>();
int currentBestScore = 0;
for (int index = 0; index < psm.getFusionCandidates().Count(); index++)
{
bool badID = false;
FusionCandidate fc = psm.getFusionCandidates()[index];
findIons(fc, psm, out string error_message1);
error_message += error_message1;
int consecutiveMissedCounter = 0;
int totalHitCounter = 0;
foreach (bool b in fc.getFoundIons())
{
if (consecutiveMissedCounter > maxMissingConsecutivePeaks) //if too many permutations possible because of an unmapped region
{
badID = true;
}
else if (!b)
{
consecutiveMissedCounter++;
}
else
{
totalHitCounter++;
consecutiveMissedCounter = 0;
} //only care about consecutive
}
bool isRepeat = false;
if (baseSequences.Contains(psm.getFusionCandidates()[index].seq))
{
isRepeat = true;
}
if (totalHitCounter > currentBestScore && !badID)//the others were worse, so delete them
{
for (int i = 0; i < index; i = 0)
{
psm.getFusionCandidates().Remove(psm.getFusionCandidates()[0]);
index--;
}
currentBestScore = totalHitCounter;
baseSequences = new List <string> {
psm.getFusionCandidates()[index].seq
};
}
else if (totalHitCounter < currentBestScore | badID | isRepeat)
{
psm.getFusionCandidates().Remove(psm.getFusionCandidates()[index]);
index--;
}
}
//If there's anything left
if (psm.getFusionCandidates().Count() > 0) //It wasn't too messy! Yay!
{
return(false);
}
else //this might be a fusion peptide, but we won't get any valuable information from this spectra, so discard it
{
return(true);
}
}
public bool GeneratePossibleSequences(PSM psm, out string error_message) //returns false if over the specified number of sequences are generated
{
error_message = "";
List <string> foundSeq = new List <string>(); //get list of all FP sequences
foreach (FusionCandidate fusionCandidate in psm.getFusionCandidates())
{
findIons(fusionCandidate, psm, out string error_message1); //populate the foundIons array
error_message += error_message1;
foundSeq.Add(fusionCandidate.seq);
}
bool done = false;
int globalIndex = 0;
while (!done)
{
done = true; //let's assume we're done and correct it later if we're not
if (psm.getFusionCandidates().Count() > maxNumPossibleSequences) //if there are more than a set number of possible sequences, this is junk and we are not searching them all
{
return(false);
}
for (int fc = 0; fc < psm.getFusionCandidates().Count(); fc++)
{
FusionCandidate fusionCandidate = psm.getFusionCandidates()[fc];
if (fusionCandidate.getFoundIons().Count() > globalIndex) //prevent crashing, use to tell when done by hitting end of fc
{
List <FusionCandidate> tempCandidates = new List <FusionCandidate>(); //fill with possible sequences
done = false; //We're not done, because at least one fusion candidate sequence length is still greater than the global index
string fusionSeq = fusionCandidate.seq;
bool[] IonFound = fusionCandidate.getFoundIons();
if (IonFound[globalIndex]) //only look for ambiguity if a peak was found to provide the stop point.
{
int mostRecent = -1; //most recent Ion found prior to this one (start point)
for (int i = 0; i < globalIndex; i++) //identify start point
{
if (IonFound[i])
{
mostRecent = i; //save most recent hit, exclusive of the current index
}
}
string ambiguousFrag = fusionSeq.Substring(mostRecent + 1, globalIndex - mostRecent);
double key = MassCalculator.MonoIsoptopicMass(ambiguousFrag, out string error_message2);
error_message += error_message2;
List <string> combinations = new List <string>();
double closestPeak = double.NaN;
var ipos = Array.BinarySearch(keys, key);
if (ipos < 0)
{
ipos = ~ipos;
}
if (ipos > 0)
{
var downIpos = ipos - 1;
// Try down
while (downIpos >= 0)
{
closestPeak = keys[downIpos];
if (closestPeak > key - productMassToleranceDa && closestPeak < key + productMassToleranceDa)
{
string[] value;
if (massDict.TryGetValue(closestPeak, out value))
{
foreach (string frag in value)
{
combinations.Add(frag);
}
}
}
else
{
break;
}
downIpos--;
}
}
if (ipos < keys.Length)
{
var upIpos = ipos;
// Try here and up
while (upIpos < keys.Length)
{
closestPeak = keys[upIpos];
if (closestPeak > key - productMassToleranceDa && closestPeak < key + productMassToleranceDa)
{
string[] value;
if (massDict.TryGetValue(closestPeak, out value))
{
foreach (string frag in value)
{
combinations.Add(frag);
}
}
}
else
{
break;
}
upIpos++;
}
}
foreach (string str in combinations)
{
string nTermSeq = fusionSeq.Substring(0, mostRecent + 1);
string cTermSeq = fusionSeq.Substring(globalIndex + 1, fusionSeq.Length - globalIndex - 1);
string novelSeq = nTermSeq + str + cTermSeq;
FusionCandidate tempCandidate = new FusionCandidate(novelSeq);
tempCandidates.Add(tempCandidate);
}
}
foreach (FusionCandidate newfc in tempCandidates)
{
if (!foundSeq.Contains(newfc.seq)) //if new FP sequence, add it.
{
foundSeq.Add(newfc.seq);
findIons(newfc, psm, out string error_message3);
error_message += error_message3;
psm.getFusionCandidates().Add(newfc);
}
}
}
}
globalIndex++;
if (psm.getFusionCandidates().Count() > maxNumPossibleSequences)
{
return(false);
}
}
return(true);
}