Characterization of Proteins in Commerical Preparations of Allergens by SDS‐Polyacrylamide Gel Electrophoresis

Abstract

Extracts of plant pollens and spores of a fungus that are used for immunotherapy of allergies were obtained commercially from Greer and analyzed for protein composition by SDS‐polyacrylamide gel electrophoresis. The extracts analyzed were pecan (Carya illinoensis), mesquite (Prosopis glandulosa), short ragweed (Ambrosia artemisiifolia), white oak (Quercus alba), mountain cedar (Juniperus ashei), and the fungus Aspergillis fumigatus. The extracts were resuspended in deionized water at a concentration of protein = 1.0 mg/ml. Samples containing 1–5 μg of protein were incubated for 2 min. at 100°C with SDS buffer and loaded on 4–20% gradient polyacrylamide gels. Electrophoresis was performed at 75 V for 2 hrs. Broad range markers (Bio‐Rad) were electrophoresed in two lanes on each gel in parallel with the samples. The gels were stained with Coomassie Brilliant Blue. The values of Mr (kDa) for the markers were 7.1, 21, 35, 49, 80, 124, and 209. The Mr (kDa) of the observed proteins for each of the allergens was determined by comparison to the migration of the markers: Carya illinoensis (10, 13, 17, 20, 27, 39, 41, 50, 51, 56, 71, 105, 119); Prosopis glandulosa (20, 27, 44, 50, 57, 63, 78, 115, 139, 146); Ambrosia artemisiifolia (16, 20, 25, 29, 42, 55, 62, 69, 84, 111); Quercus alba (12, 23, 40, 44, 63, 115, 135, 141) Juniperus ashei (14, 25, 37, 51, 66); Aspergillis fumigatus (10, 24, 27, 51, 59, 79, 85, 91, 100, 108, 124, 129, 140). The extracts will be fractionated in order to isolate and identify the proteins responsible for allergic reactions. This work was supported by a grant from the Welch Foundation to the Department of Chemistry at University of the Incarnate Word and by CA74388 to PDF.