Hi Kristina, I’m not certain I fully understand your issue, but maybe I can answer some questions:
Partial old: Name: DIETIIQK/2 *(old entry, original library)* 308.1581 226.5 ? 309.0826 359.4 ? 325.6734 1596.8 b6-35^2/0.000,b6-36^2/0.492 329.1945 141.2 a6^2/0.000 343.1920 668.4 b6^2/0.000,y3-45/-0.042,y6-45^2/-0.516,y6-46^2/-0.024 Partial new: Name: DIETIIQK/2 *(new entry, combined library)* 308.1581 226.5 ? 309.0826 359.4 ? 326.1680 1596.8 ? 328.2231 141.2 m4:6/0.000 344.1816 668.4 m3:5/0.000 The first two peaks are fine. For the third entry, I am guessing that in the original library this peak got shifted to exact m/z of the presumed interpretation b6-35^2. But this is a highly unlikely interpretation. So in the new entry, that peak retains its original m/z (i.e. not snapped to a presumed interpretation) and a “?”. SpectraST seems to be smarter about not assigning a silly interpretation. For the next peak with intensity 141.2, the old library had an interpretation of a6^2 and the m/z is snapped to that interpretation. But a6^2 is a super unlikely interpretation, or maybe let’s call it impossible and wrong. In the new library, this same peak has been interpreted as an internal fragmentation ion and the m/z has been snapped to that. The m4:6 means that the peptide was fragmented in two places such that you get a little ion that is TII and has a charge so you see it. Internal fragmentation turns out to be fairly common and so m4:6 is far more plausible an interpretation than a6^2. Same for m3:5 (ETI). Not necessarily correct, but far more plausible than an a6^2 and a b6^2. So I’m guessing that the first spectrum comes from a version where internal fragmentation was not yet supported, and the second spectrum comes from a newer version of SpectraST that knows about internal fragmentation and interprets peaks better. Does that seem like a reasonable explanation of what’s going on? Henry might know more. Regards, Eric *From:* [email protected] <[email protected]> *On Behalf Of *Kristina Plate *Sent:* Friday, September 20, 2019 6:22 AM *To:* spctools-discuss <[email protected]> *Subject:* [spctools-discuss] Combination of consensus libraries and import in MRM format via spectraST Hello again, as I described before (topic: *What happens during consensus building?*) I have a problem with some messed up spectra in my spectral libraries. I combined four spectral libraries and built consensus spectra. Afterwards I reimported the combined consensus spectral library in MRM format and converted it in an assay library. When I checked the SPTXT file I found some *slightly changed spectra* and new *"ion types" m*. Please see my example of an old, normal spectrum and the corresponding new one below: Name: DIETIIQK/2 *(old entry, original library)* LibID: 4160 MW: 960.5481 PrecursorMZ: 480.2740 Status: Normal FullName: X.DIETIIQK.X/2 (CID-QTOF) Comment: AvePrecursorMz=480.5611 BinaryFileOffset=23385298 FracUnassigned=0.09,1/5;0.23,11/20;0.06,7/31 MassDiff=-0.0014 Mods=0 NAA=8 NISTProtein=Id_02 NMC=0 NTT=1 Nreps=1/1 OrigMaxIntensity=11 Parent=480.274 Pep=Tryptic PrecursorIntensity=0 Prob=1.0000 Protein=1/Id_02 RawSpectrum=file_02_04.69683.69683 RetentionTime=2745.2,2745.2,2745.2 Sample=1/sample_02,1,1 Se=1^C1:pb=1.0000/0,fv=2.7040/0 Spec=CREATE TotalIonCurrent=8.9e+003 iRT=33.4,33.4,33.4 NumPeaks: 31 308.1581 226.5 ? 309.0826 359.4 ? 325.6734 1596.8 b6-35^2/0.000,b6-36^2/0.492 329.1945 141.2 a6^2/0.000 343.1920 668.4 b6^2/0.000,y3-45/-0.042,y6-45^2/-0.516,y6-46^2/-0.024 353.2183 967.7 y3-35/0.000 354.2183 480.9 y3-35i/0.000 355.2183 481.6 y3-35i/0.000 358.1609 442.5 b3/0.000,y6-17^2/0.456,y6-18^2/0.948 358.1970 96.7 ? 365.2030 293.0 ? 373.2367 296.2 ? 388.2554 1744.6 y3/0.000,b7-36^2/-0.955 424.1714 315.8 b4-35/0.000,b4-36/0.984 442.1820 644.1 b4-17/0.000,b4-18/0.984 457.7633 546.4 p-45^2/0.000,p-46^2/0.492,y4-44/0.414 458.2791 109.5 p-44^2/0.000,b4/-0.929 471.7608 110.9 p-17^2/0.000,p-18^2/0.492 472.2608 111.1 p-17^2i/0.000 477.1321 111.6 ? 480.2740 336.0 p^2/0.000 484.3130 224.9 y4-17/0.000,y4-18/0.984 501.3395 523.5 y4/0.000 553.1674 240.4 ? 567.3501 487.3 y5-35/0.000 584.3766 247.1 y5-18/0.000 602.3872 2935.1 y5/0.000 696.3927 205.5 y6-35/0.000,y6-36/0.984 714.4032 2211.4 y6-17/0.000,y6-18/0.984 731.4298 10000.0 y6/0.000 732.4298 414.9 y6i/0.000 Name: DIETIIQK/2 *(new entry, combined library)* LibID: 4673 MW: 960.5481 PrecursorMZ: 480.2740 Status: Normal FullName: X.DIETIIQK.X/2 (CID-QTOF) Comment: AvePrecursorMz=480.5611 BinaryFileOffset=20613807 FracUnassigned=0.09,1/5;0.25,13/20;0.17,13/31 MassDiff=-0.0014 Mods=0 NAA=8 NISTProtein=Id_02 NMC=0 NTT=1 Nreps=1/1 OrigMaxIntensity=11 Parent=480.274 Pep=Tryptic PepContext=1/NTPR_DIHE PrecursorIntensity=0 Prob=1.0000 Protein=1/Id_02 RawSpectrum=file_02_04.69683.69683 RetentionTime=2745.2,2745.2,2745.2 Sample=1/sample_02,1,1 Se=1^C1:pb=1.0000/0,fv=2.7040/0 Spec=CREATE TotalIonCurrent=8.9e+003 iRT=33.4,33.4,33.4 NumPeaks: 31 308.1581 226.5 ? 309.0826 359.4 ? 326.1680 1596.8 ? 328.2231 141.2 m4:6/0.000 344.1816 668.4 m3:5/0.000 353.2183 967.7 y3-35/0.000 354.2183 480.9 y3-35i/0.000 355.2183 481.6 y3-35i/0.000,m5:7/-0.016 358.1609 442.5 b3/0.000 358.1970 96.7 ? 365.2030 293.0 ? 373.2367 296.2 ? 388.2554 1744.6 y3/0.000 424.1714 315.8 b4-35/0.000 441.1980 644.1 b4-18/0.000 457.2713 546.4 p-46^2/0.000,m3:6/0.006 459.2086 109.5 b4/0.000 471.2688 110.9 p-18^2/0.000 472.2512 111.1 ? 477.1321 111.6 ? 480.2410 336.0 ? 484.3130 224.9 y4-17/0.000 501.3395 523.5 y4/0.000 553.1674 240.4 ? 568.3124 487.3 ? 584.2763 247.1 ? 602.3872 2935.1 y5/0.000 695.4087 205.5 y6-36/0.000 713.4192 2211.4 y6-18/0.000 731.4298 10000.0 y6/0.000 732.4675 414.9 ? I assumed before, that it was an issue with the consensus building, but I figured out that it took action during the *import via spectraST into MRM format*. Now, I just saw that I don't have this problem when I use the single libraries. Even with consensus libraries built with with an older spectraST version the MRM import works just fine. Maybe there is the *problem in the combination of the spectral libraries?* I already got them as single consensus libraries and combined them with the following command spectrast -cNcombined_lib -cd -cu -cr1 -cy1 -cAC -cJU Lib_01.splib Lib_01.splib Lib_01.splib Lib_01.splib Could this be an issue here. Do I have to rebuild all libraries before combining them? I would be really happy about any suggestions. Thank you in advance! Kind regards, Kristina ____________________ Kristina Plate, MSc. Biomathematics University of Greifswald Center for Functional Genomics of Microbes Institute for Microbiology Department of Microbial Proteomics Felix-Hausdorff-Str. 8 17489 Greifswald phone: +49 3834 420-5925 fax: +49 3834 420-5902 -- You received this message because you are subscribed to the Google Groups "spctools-discuss" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/spctools-discuss/1573a2bc-1b4a-4ca7-bc88-75579028df95%40googlegroups.com <https://groups.google.com/d/msgid/spctools-discuss/1573a2bc-1b4a-4ca7-bc88-75579028df95%40googlegroups.com?utm_medium=email&utm_source=footer> . -- You received this message because you are subscribed to the Google Groups "spctools-discuss" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. 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