Figure 7: MALDI QIT ToF MS/MS spectrum of the ion signal at m/z 1240.01 (c.f Figure 6A). The determined partial amino acid sequence is depicted and was assigned to an RA33 peptide comprising amino acids 85–95. The mass spectrometric fragment ions from the Y ״ type ion series and the B type ion series are indicated. Loss of ammonia and loss of water, respectively, is indicated. DHB was used as a matrix.