Purification of a 41 kDa cod-allergenic protein.
Cod fish is one of the foods most frequently involved in allergy. Only the cod allergen Gad c I, a 12.3 kDa parvalbumin, has been purified and characterized. Recently, we have detected allergen bands which have not previously been described, in particular a 41 kDa protein, by Western-blot. In the present work, this protein has been purified from a crude cod extract by ammonium sulfate fractionation, hydroxyapatite chromatography and preparative electrophoresis; a single band with an Mr of 41 x 10(3) was found in silver-stained sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The amino acid composition and the isoelectric point of the protein were determined. The purified protein (p41) was shown to bind specifically to reaginic IgE from sera of cod-allergic individuals and to a monoclonal anti-parvalbumin which recognizes specifically the first calcium binding site of parvalbumins. p41 may therefore contain a calcium binding site corresponding to an IgE-epitope similar to that of Gad c I.
Galland
A V
AV
Laboratoire de Pathologie Cellulaire et Moléculaire en Nutrition, EP CNRS 0616, Faculté de Médecine, Vandoeuvre-lès-Nancy, France.
Dory
D
D
Pons
L
L
Chopin
C
C
Rabesona
H
H
Guéant
J L
JL
Fleurence
J
J
D000485:Allergens / Q000302:isolation & purification*; D000596:Amino Acids / Q000032:analysis; D000645:Ammonium Sulfate; D000818:Animals; D002845:Chromatography; D017886:Durapatite; D004586:Electrophoresis; D004591:Electrophoresis, Polyacrylamide Gel; D005399:Fishes; D005512:Food Hypersensitivity; D005590:Fractional Precipitation; D006863:Hydrogen-Ion Concentration; D008970:Molecular Weight; D011506:Proteins / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification*; D016622:Silver Staining
D000485:Allergens; D000596:Amino Acids; D011506:Proteins; D017886:Durapatite; D000645:Ammonium Sulfate