Comparison of fragment ion annotation using NRP-Annotation or mMass.

Indicated are the percentage of the ion intensity annotated as well as the number of ions matched by the software vs. the total ion number. MC = Microcystin, CM = Cyclomarin, CRY = Cryptophycin, MG = Microginin. *options chosen that reflect the fragments NRP-Annotation can calculate (a- and b-ions, -NH3 and -H2O, Allow Scrambling, including b1 ions). **all available options chosen. ***if 37Cl isotope peaks are manually deleted: 88%, 21 of 32. m/z tolerances used for matching calculated to experimentally observed fragments: 10.015 Da, 20.2 Da, 30.1 Da.