title: Dynorphin A(1-8) in human placenta: amino acid sequence determined by tandem mass spectrometry.
abstract: Presence of the kappa receptor-preferring neuropeptide dynorphin A(1-8) in human placenta has been demonstrated by mass spectrometry to establish rigorously the appropriate molecular weight and amino acid sequence. Liquid secondary ionization mass spectrometry produced the protonated molecule ion, (M + H)+, at m/z 981 of the endogenous peptide, and tandem mass spectrometry collected the product ion spectrum that contained the appropriate amino acid sequence-determining fragment ions produced from the precursor ion (M + H)+. The amino acid sequence of the peptide is YGGFLRRI.
mesh_terms: D000595:Amino Acid Sequence; D002824:Chorionic Villi / Q000737:chemistry*; D004399:Dynorphins / Q000737:chemistry / Q000302:isolation & purification*; D005260:Female; D006801:Humans; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000302:isolation & purification*; D011247:Pregnancy; D011257:Pregnancy Proteins / Q000737:chemistry / Q000302:isolation & purification*; D011863:Radioimmunoassay; D011869:Radioligand Assay; D018629:Spectrometry, Mass, Secondary Ion
chemical_list: D010446:Peptide Fragments; D011257:Pregnancy Proteins; D004399:Dynorphins; C026770:dynorphin (1-8)