Yes, that is the m/z error and ^3 means triply charged. So: > > 147.1406 92.5 y1/0.03,y4-35^3/-0.61,y4-36^3/-0.28
Means that the peak at 147.1406 could be a y1 ion where the difference between the observed 147.1406 and the expected for y1 is 0.03 Daltons. But the peak could also be explained by a triply charged y4 ion with a neutral loss of -35, but the variance is -0.61 (so this is less likely to be the explanation of the peak). Or is could be a triply charged y4 ion with loss of -36 with -0.28 variance. A list of neutral losses can be found here: http://www.i-mass.com/guide/neutral.html Although not all are supported by SpectraST. A description of all losses supported by SpectraST will be forthcoming in the SpectraST documentation. Cheers, Eric > -----Original Message----- > From: [email protected] [mailto:spctools- > [email protected]] On Behalf Of Matt Chambers > Sent: Friday, November 26, 2010 6:30 AM > To: [email protected] > Subject: Re: [spctools-discuss] Interpreting SpectraST *.sptxt files > > I'm pretty sure it indicates m/z error of the matched peak with the > theoretical > m/z. I'm not sure what the ^3 means though. > > -Matt > > > On 11/25/2010 9:32 PM, GATTACA wrote: > > Hello. > > > > Can someone explain to me the syntax in of the peaklists as they are > > reported in the SpectraST *.sptxt file? > > I understand that the *.sptxt file is a text version of the binary > > *.splib file. > > > > For instance, consider this snippet from the *.sptxt file I created > > from some searched results. > > 147.1406 92.5 y1/0.03,y4-35^3/-0.61,y4-36^3/-0.28 > > 157.9838 197.0 b5-35^3/-0.43,b5-34^3/-0.76 > > 182.0084 129.3 y3^2/-0.09 > > 187.1618 112.0 y5-17^3/0.39,y5-18^3/0.71 > > 192.9816 360.4 y5^3/0.53,a4^2/0.86,b6-45^3/-0.45 > > 206.2740 321.2 b4^2/0.16 > > 213.0517 195.2 y2-35/-0.07,y2-36/0.91 > > 223.2085 118.6 ? > > > > I interpret the '?' to mean an unmatched peak to the peptide. > > Now in the first line of the above example (y1/0.03, y4-35^3/-0.61, > > y4-36^3/-0.28). Is this indicating that this peak corresponds to the > > first y-ion? or y-ion#4 ? What does the value after the slash mean? > > > > Any and all help is appreciated. > > Thanks > > -- > You received this message because you are subscribed to the Google > Groups "spctools-discuss" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to spctools- > [email protected]. > For more options, visit this group at > http://groups.google.com/group/spctools-discuss?hl=en. -- You received this message because you are subscribed to the Google Groups "spctools-discuss" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/spctools-discuss?hl=en.
