Dear,
This difference exists but does not affect the software results. Specifically, the
mass of Label_13C(6)[R] is provided by Unimod, and the mass of SILAC_Arg6 added by
user is obtained by pConfig by calculating the atomic mass.
Best,
Kaifei Wang
I notice that the same modification (same composition) calculated by pConfig is
slightly different from the default one. I modified the isotope mass in
element.ini based on your article (https://doi.org/10.52601/bpr.2021.210004) but
the mass difference is still there.