Hi,

thanks a lot for developing TPP, it's a great set of tools.

I'm trying to analyze DDA data (Top 5 method) from a Waters Xevo QTOF but 
there seems to be a problem with identifying MSMS spectra in the mzml files 
generated from the .raw folders through MSconvert, which is likely caused 
by multiple MSMS spectra stored in different "functions" having the same 
spectra index. 

The Comet or X!tandem search completes without errors but the spectra 
number being searched is only about half of all MSMS spectra in the file 
and the spectra linked in the pep.xml don't fit with the identifications 
(in terms of matching fragments and precursor mass). When I process the raw 
data in PLGS and export as MGF, followed by conversion to mzml in 
MSconvert, the scans get a function-independent consecutive index and the 
search results seem to be correct. While this is fine for peptide 
identification, PLGS doesn't allow me to export the MS1 spectra that I need 
for the down-stream quantification. So it's not a viable alternative.

Can TPP handle a two dimensional spectra index (Function=x Spectrum=y)? Or 
can I set MSconvert to generate a one-dimensional index that preserves the 
association between MS1 and MS2 spectra of each DDA cycle? I ran MSconvert 
with the "write index" option but that doesn't seem to generate such an 
index.

Thank you for your help,

David Schmidt

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