Protein components of low-density lipoproteins purified from hen egg yolk.
To identify apoproteins present in purified low-density lipoproteins from hen egg yolk in relation with their emulsifying properties, they have been separated by SDS-PAGE. We identified two different proteins by liquid chromatography-tandem mass spectrometry analysis of the peptides obtained by the trypsin digestion of protein gel bands. Apovitellenin I was identified as a monomer and a dimer. Its amino acid sequence was totally confirmed, and molecular mass determination by liquid chromatography-mass spectrometry showed that it did not present post-translational modifications but only a slight heterogeneity by the loss of one or two amino acids at the C-terminal part of the protein. Apolipoprotein B was identified into seven bands corresponding to fragments resulting of a processing of the hen blood apo-B protein. The identity of the fragments was determined by the observation of the sequence coverage by trypsin peptides and the sequence alignment with homologous human blood apolipoprotein B-100.
Jolivet
P
P
Institut National de la Recherche Agronomique, Institut National Agronomique Paris-Grignon, UMR 206, Laboratoire de Chimie Biologique, Centre de Biotechnologie Agro-Industrielle, 78850 Thiverval-Grignon, France. jolivet@grignon.inra.fr
Boulard
C
C
Beaumal
V
V
Chardot
T
T
Anton
M
M
D000595:Amino Acid Sequence; D000818:Animals; D001055:Apolipoproteins B / Q000032:analysis / Q000737:chemistry; D001059:Apoproteins / Q000032:analysis* / Q000737:chemistry; D002645:Chickens; D002853:Chromatography, Liquid; D019281:Dimerization; D015387:Egg Proteins, Dietary / Q000032:analysis; D004530:Egg Yolk / Q000737:chemistry*; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D008077:Lipoproteins, LDL / Q000737:chemistry*; D013058:Mass Spectrometry
D001055:Apolipoproteins B; D001059:Apoproteins; D015387:Egg Proteins, Dietary; D008077:Lipoproteins, LDL; C018456:apovitellenin