Isolation and characterization of beta-gliadin fractions.

beta-Gliadins of Cappelle wheat are distributed in three subsets in starch gel electrophoresis at pH 3.2, Six of these beta components have been isolated by sulfopropyl-Sephadex C-50 chromatography, gel filtration on Sephadex G-100 and sulfoethyl-cellulose chromatography. Apparent molecular weights determined by gel filtration and SDS-polyacrylamide gradient gel electrophoresis are between 29 000 and 35 000. Valine is the N-terminal amino acid of all beta-gliadins with the exception of the slowest component in electrophoresis at pH 3.2 the N-terminal amino acid of which is asparagine. The main difference between the amino acid compositions is the lack of tryptophan in the fastest of the three component subsets visible in electrophoresis at pH 3.2.