Post-translational phosphorylation affects the IgE binding capacity of caseins.
IgE response specific to those molecular regions of casein that contain a major phosphorylation site was analyzed using native and modified caseins and derived peptides. This study included (i) the naturally occurring common variants A1 and A from beta- and alphas2-caseins, respectively, which were purified in the native form and then dephosphorylated, (ii) a purified rare variant D of alphas2-casein which lacks one major phosphorylation site, and (iii) the native and dephosphorylated tryptic fragment f(1-25) from beta-casein. Direct and indirect ELISA using sera from patients allergic to milk showed that the IgE response to caseins is affected by modifying or eliminating the major phosphorylation site.
Bernard
H
H
Laboratoire d'Immuno-Allergie Alimentaire, INRA-CEA, SPI, Bâtiment 136, Saclay, 91191, Gif sur Yvette, France. bernardh@dsvidf2.cea.fr
Meisel
H
H
Creminon
C
C
Wal
J M
JM
D001665:Binding Sites; D002364:Caseins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000737:chemistry; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood / Q000737:chemistry*; D016269:Milk Hypersensitivity / Q000097:blood; D010766:Phosphorylation; D020033:Protein Isoforms / Q000737:chemistry; D011499:Protein Processing, Post-Translational; D014357:Trypsin
D002364:Caseins; D000939:Epitopes; D020033:Protein Isoforms; D007073:Immunoglobulin E; D014357:Trypsin