Bovine actin mass list generated from mass processing. Mass list from bovine actin samples are aligned in columns in a spreadsheet. Red masses are actin peptide fragments, gray masses are trypsin products, blue masses do not match the enzymatic peptide digest profile for actin, but are present in greater than 60% of the samples, and white masses do not match the enzymatic peptide digest profile for actin, but are not present in greater than 60% of the samples.