Matrix-assisted laser desorption/ionization time-of-flight mass spectrometric observation of a peptide triplet induced by thermal cleavage of cystine.
Heat-induced (90 degrees C, 30 min) beta-elimination of a cystine residue leads to cleavage of a disulfide bond and produces a set of three peptides with a cysteine residue, a thiocysteine residue (+32Da), and a dehydroalanine residue (-34Da). This characteristic feature was observed from somatostatin and insulin by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Mass spectrometric observation of this triplet is useful in identifying the presence of a cystine residue in a peptide, and could assist mass spectrometric identification of the peptide from a database.
Kim
J S
JS
School of Chemistry and Molecular Engineering, Seoul National University, Seoul, Korea 151-747.
Kim
H J
HJ
D000595:Amino Acid Sequence; D003553:Cystine / Q000737:chemistry*; D004220:Disulfides / Q000737:chemistry; D006358:Hot Temperature; D007328:Insulin / Q000737:chemistry; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000032:analysis* / Q000737:chemistry; D020543:Proteome / Q000032:analysis / Q000737:chemistry; D013004:Somatostatin / Q000737:chemistry; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D004220:Disulfides; D007328:Insulin; D010446:Peptide Fragments; D020543:Proteome; D003553:Cystine; D013004:Somatostatin