PURIFICATION AND CHARACTERIZATION OF THE GLUTENIN SUBUNITS OF TRITICUM-TAUSCHII, PROGENITOR OF THE D-GENOME IN HEXAPLOID BREAD WHEAT

N-terminal amino acid sequences and sodium dodecyl sulfate polyacrylam ide gel electrophoresis (SDS-PAGE) molecular weights have been determi ned for high-performance liquid chromatography (HPLC)-purified high mo lecular weight (HMW) and low molecular weight (LMW) glutenin subunits (GS) of Triticum tauschii sap. strangulata, contributor of the D genom e to hexaploid bread wheat. The use of three different extraction proc edures resulted in similar glutenin preparations. On the basis of N-te rminal sequences, the same types of glutenin subunits that have been r eported in bread and durum wheats (HMW-GS of both the x and y types an d LMW-GS of the LMW-s, LMW-m, alpha-, and gamma-types) were found in T . tauschii. However, the HMW-GS in T. tauschii were in greater proport ion relative to LMW-GS when compared to reported values for a bread an d durum wheat. Our results support the likelihood that differences in the proportions of the various subunits contributed by the A, B, and D genomes, rather than qualitative differences in the types of subunits , are responsible for the major differences in quality characteristics between bread wheat and durum wheat.