Identification of erythro-beta-hydroxyasparagine in the EGF-like domain of human C1r.
Previous studies [(1987) Biochem. J. 241, 711-720] have shown that position 150 of human C1r is occupied by a modified amino acid that, after acid hydrolysis, yields erythro-beta-hydroxyaspartic acid. In view of further investigations on the nature of this residue, peptide CN1a T8/T9 TL8 (positions 147-155) was isolated from C1r A chain by CNBr cleavage followed by enzymatic cleavages by trypsin and thermolysin. Amino acid analysis, sequential Edman degradation and FAB-MS of this peptide indicate that the residue at position 150 is an erythro-beta-hydroxyasparagine resulting from post-translational hydroxylation of asparagine.
Arlaud
G J
GJ
Département de Recherches Fondamentales, Unité INSERM 238, CEN-Grenoble 85 X, France.
Van Dorsselaer
A
A
Bell
A
A
Mancini
M
M
Aude
C
C
Gagnon
J
J
D000596:Amino Acids / Q000032:analysis; D001216:Asparagine / Q000031:analogs & derivatives* / Q000032:analysis; D003166:Complement Activating Enzymes; D003172:Complement C1; D015923:Complement C1r; D004815:Epidermal Growth Factor; D006801:Humans; D013058:Mass Spectrometry; D010446:Peptide Fragments / Q000032:analysis; D013820:Thermolysin; D014357:Trypsin
D000596:Amino Acids; D003172:Complement C1; D010446:Peptide Fragments; C050931:3-hydroxyasparagine; D004815:Epidermal Growth Factor; D001216:Asparagine; D003166:Complement Activating Enzymes; D014357:Trypsin; D015923:Complement C1r; D013820:Thermolysin