Micropurification and amino acid sequence of beta-casomorphin-8 in milk from a woman with postpartum psychosis.
Milk was obtained from a woman with acute postpartum psychosis and with ongoing lactation. Defatted samples were subjected to micropurification and collected fractions were analyzed by means of their beta-casomorphin-8 immunoreactivity. Immunoreactive material with the same chromatographic properties as synthetic human beta-casomorphin-8 was determined by amino acid sequence analysis to be Tyr-Pro-Phe-Val-Glu-Pro-Ile-Pro. Its molecular mass was determined by fast atom bombardment-mass spectrometry to be 962.3 Da. These determinations, which ultimately identify the immunoreactive material as human beta-casomorphin-8, represent the first structural identification of a beta-casomorphin peptide from a body fluid.
Renlund
S
S
Pharmacia LKB Biotechnology AB, Uppsala, Sweden.
Erlandsson
I
I
Hellman
U
U
Silberring
J
J
Wernstedt
C
C
Lindström
L
L
Nyberg
F
F
D000208:Acute Disease; D000595:Amino Acid Sequence; D004723:Endorphins / Q000737:chemistry / Q000302:isolation & purification*; D005260:Female; D006801:Humans; D013058:Mass Spectrometry; D008832:Microchemistry; D008895:Milk, Human / Q000737:chemistry*; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000302:isolation & purification*; D011618:Psychotic Disorders / Q000378:metabolism*; D011644:Puerperal Disorders / Q000378:metabolism*
D004723:Endorphins; D010446:Peptide Fragments; C055518:beta casomorphin 8 protein, human