SDS-PAGE analysis revealed that what was considered the major protein of beer is actually formed by two polypeptides with the same molecular mass (-40 kDa), but different hydrodynamic volumes in their incompletely unfolded conformation. The two polypeptides share common properties, although the one with the more open conformation is associated with sugars, whereas the other is not. Immunoblotting experiments with polyclonal antibodies raised against the two electrophoretically purified polypeptides indicated that they are immunologically related and allowed the identification of their precursors in barley grain. These latter are two heat-resistant albumins whose electrophoretic behavior corresponded to that of beer proteins. These two albumins coincide with protein Z, the first member of the serpin superfamily described in plants.

No abstract

No abstract

Reduced alkylated glutenin subunits from wheat flour were fractionated by preparative electrophoresis at acid pH. The high molecular weight glutenin subunits (HMW-GS) and some of the low molecular weight glutenin subunits (LMW-GS) were purified by this one-step procedure, whereas the remainder of the LMW-GS, comigrating in the acid system, were purified in a second step by electroendosmotic preparative electrophoresis in the presence of sodium dodecyl sulfate. The quantities of recovered protein were sufficient for biochemical characterization and/or antibody production.

Polyclonal antibodies have been raised against a highly purified egg yolk protein, which appears to be unaffected by thermal treatments and whose content is constant in eggs of different origin. The antibodies are able to bind specifically to the egg yolk protein and can be used for the quantification of the egg content in egg pasta. For this purpose an indirect ELISA procedure has been developed.