Fig. 4.

Same peptide contributed to identification of tubulin β in amniotic fluid and gastric aspirates. A, the annotated spectrum that matches the +2 charged peptide NSSYFVEWIPNNVK in the amniotic fluid. B, the annotated spectrum that matches the +2 charged peptide NSSYFVEWIPNNVK in the gastric aspirates. The peaks colored in red are b-ions and the neutral losses associated with the b-ions; the peaks colored in blue are y-ions and the neutral losses associated with the y-ions. However, b-ions and y-ions are annotated. (The high peak near b9+ (at m/z 1126.38) in B occurs at m/z 1127.35, i.e. within the 1-Da range.)