You can use from one to three of the Excluded Peptide Modification parameters of the Reporter Ions Quantifier node and the Precursor Ions Quantifier node to determine the peptides to exclude from the rollup from the peptide group quantification results to the protein level.

The following figure shows how to select a modification and the abbreviation of the amino acid to determine what peptides to exclude from the normalization calculation.

Excluded Peptide Modification parameters of the Reporter Ions Quantifier or the Precursor Ions Quantifier node
Excluded Peptide Modification parameters of the Reporter Ions Quantifier or the Precursor Ions Quantifier node