P2P proteomics -- data sharing for enhanced protein identification

Table 1 Similarity table for peptide modification

modification code	-1	1	2	3	5	31	32	89	90
-1	1
1	1	1
2	1	0	1
3	1	0	1	1
5	1	0	1	1	1
31	1	0	1	1	1	1
32	1	0	1	1	1	1	1
89	1	1	0	0	0	0	0	1
90	1	1	0	0	0	0	0	0	1

-1 = nothing; 1 = oxidation of M; 2 = carboxymethyl C; 3 = carbanidomethyl C; 5 = propionamide C; 31 = carbamylation of K; 32 = carbamylation of n-trem peptide; 89 = oxidation of H; 90 = oxidation of W. For the remaining codes the similarity is 1 if they are equal and 0 if the are not equal.