Determination of the amino acid sequence of apamin by tandem mass spectrometry.
A new strategy has been developed for the determination of the amino acid sequence of apamin, a two disulfide-bond neurotoxic oligopeptide. Relative molecular mass up to about 2000 was determined using electrospray mass spectrometry. This technique shows that three basic amino acid residues are present in apamin. A hydrophobic tryptic digest fragment was sequenced using fast-atom bombardment combined with tandem mass spectrometry. But the full sequence has been directly observed using a tandem mass spectrometer: the daughter-ion mass spectrum of protonated molecules of dithiothreitol-reduced apamin gives the sequence.
lange
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Laboratoire de Spectrométrie de Masse, IFRMP-INSERM-CNRS-Université de Rouen, Mont Saint Aignan, France.
Marvin
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L
Marcual
A
A
Ordsmith
N
N
Bordoli
R S
RS
D000595:Amino Acid Sequence; D001030:Apamin / Q000032:analysis*; D004229:Dithiothreitol; D006868:Hydrolysis; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D008970:Molecular Weight; D014357:Trypsin
D001030:Apamin; D014357:Trypsin; D004229:Dithiothreitol