Performance of the target and alternative k-permuted decoy databases used with the Crux database search program using spectra from 80 unmodified neuropeptides.

aTarget: database of 236 neuropeptide sequences; K103: k-permuted decoy database size of 236,000 peptides; K104: k-permuted decoy database size = 2,360,000 peptides; K105: k-permuted decoy database size = 23,600,000 peptides; K106: k-permuted decoy database size = 236,000,000 peptides.
b# ions: permutation p-values computed for the number of matched b- and y-ions. XCorr: permutation p-values computed from the XCorr scores of the matches. Sp: permutation p-values computed from the Sp scores of the matches. ΔCn: permutation p-values computed using X! Tandem ΔCn.
cSignificance threshold (t) for matched to be considered significant at p-value<1×10−t.
dCumulative number of peptides with p-values thresholds of 1×10−2 and 1×10−4.
Performance of the target and alternative k-permuted decoy databases used with the Crux database search program using spectra from 80 unmodified neuropeptides.